The prohibition on assistance, encouragement, or inducement
The prohibition on assistance, encouragement, or inducement of prohibited activities is the provision of the TPNW that is contravened by the greatest number of states. Based on available information, the Nuclear Weapons Ban Monitor has concluded that all states parties and signatories were compliant, while 36 states not party engaged in conduct in 2021 that was not compatible with this prohibition. They aid and abet other states’ retention of nuclear weapons in multiple ways, as discussed under headings A) to I) below. Given the secrecy surrounding military activities, the information is likely incomplete.
ARTICLE 1(1)(e) - INTERPRETATION
Each State Party undertakes never under any circumstances to: ‘Assist, encourage or induce, in any way, anyone to engage in any activity prohibited to a State Party under this Treaty.’
• Under this Article, a state party is precluded from assisting any other state, alliance, or international organisation, company, non-state group, or individual to develop, test, produce, manufacture, otherwise acquire, possess, stockpile, transfer, deploy, receive, threaten to use, or use nuclear weapons or other nuclear explosive devices.
• States parties to the TPNW are allowed to participate in security alliances and military cooperation arrangements with nuclear-armed states — and may continue to carry out all planning, operations, exercises, and other military activities with them — so long as this does not involve nuclear weapons. Participation in nuclear-weapon-related military activities, however, would need to be discontinued.
• Several other longstanding disarmament treaties contain a similarly worded prohibition, and there is an established understanding of the concepts of assistance, encouragement, and inducement in international law.
• The term ‘in any way’ does not materially alter the scope of the provision. Conduct by act or omission would be covered by this prohibition irrespective of the words ‘in any way’.
• The effects of violating this prohibition are identical, regardless of which alternative has been violated. If an act is clearly assistance, it is superfluous to determine whether the act also constitutes encouragement, and vice versa.
• Unlike the Chemical Weapons Convention (CWC), the TPNW does not contain a broad prohibition on ‘military preparations to use’ nuclear weapons. (Nor do the Anti-Personnel Mine Ban Convention (APMBC) and the Convention on Cluster Munitions (CCM).) However, the object and purpose of the TPNW, as well as its negotiating history, leave nothing to suggest that this omission of a provision on military preparations was meant to exclude such activities from the scope of the Treaty. For the nuclear-armed states themselves, military preparations are rendered illegal under the TPNW through the prohibition on possession and stockpiling. When non-nuclear-armed states participate in such activities together with nuclear-armed states, this is rendered unlawful by the prohibition on assisting, encouraging or inducing a prohibited activity.
• In order for conduct to constitute assistance, there must be a causal link between the conduct and a prohibited activity. In addition, the conduct must contribute significantly to this activity, although it does not need to be essential to its occurrence. Insignificant contributions would not constitute prohibited assistance. Inherent in the requirement that the contribution is significant is that the prohibited activity which is assisted must be ongoing or temporally proximate. This means that it need not have happened or be ongoing, but cannot just be a theoretical possibility.
• The state must have acted with the knowledge that the conduct would, in the ordinary course of events, assist a prohibited activity. This effectively excludes temporally remote or incidental contributions.
• The forms of assistance that are unlawful can be, among others, financial (such as through economic assistance for nuclear-weapon production); technological (for example, by the export of equipment/components for such production); operational (for instance, by conventional military support for nuclear bombing); technical (through the provision of expert information); or human (such as by seconding nuclear scientists to assist in another state’s nuclear-weapon programme).
• Encouraging in the context of the TPNW means persuading or seeking to persuade any other state or any legal or natural person to carry out a prohibited activity or continue an ongoing violation of any of the Article 1 prohibitions.
• The prohibited activity being encouraged does not need to materialize as it is the act of encouragement that is prohibited and not the result.
• Encouragement could take the form of verbal, written, material, or institutional support, whether from a government as such (for instance, through the adoption of a particular policy or document) or from pertinent senior government or military officials. Where such support has been given, the encouragement is understood to be ongoing until the point at which it is clearly withdrawn.
• Inducing a prohibited activity means offering someone something in exchange for the performance of that activity. Thus, inducing will always involve encouragement.
• In some cases, it may not be possible to conclude that a specific practice or capability in a given state presently amounts to assistance or encouragement of a prohibited act under the TPNW, while it is clear that it may well do so in the future.
• For umbrella states considering which changes they would need to implement in order to ensure compatibility with the TPNW, the central issue is whether maintaining a particular practice or capability would run counter to the object and purpose of the TPNW – which is to ensure that nuclear weapons are never again used under any circumstances. (See TPNW, preambular paragraph 2.)
• Article 5 of the TPNW also obligates each state party to take all appropriate legal, administrative and other measures to prevent and suppress prohibited activities undertaken by persons or on territory under its jurisdiction or control. There is a general obligation under international law to implement treaties adhered to in good faith.
A) Participation in nuclear strike exercises and joint manoeuvres
Assisting nuclear bombing raids or strikes, for instance with conventional air tactics, would undoubtedly constitute unlawful assistance to use nuclear weapons. Participation in exercises that involve the simulated use of nuclear weapons also contravenes Article 1(1)(e) of the TPNW. Specifically, participation in nuclear strike exercises would, in most conceivable scenarios, amount to encouragement of possession and development. After all, practising nuclear-weapon use implies an endorsement of the potential use of the weapons in the future and, by extension, an encouragement of the possession of nuclear weapons in the present. Nuclear-weapon-use exercises are frequently conducted precisely with a view to building collective resolve and commitment to continued possession as well as for potential use of nuclear arms in certain circumstances.
Czechia, Poland, and the five nuclear host states in NATO (Belgium, Germany, Italy, the Netherlands, and Turkey) all encouraged possession of nuclear weapons when, in October 2021, they participated in NATO’s annual nuclear strike exercise, ‘Steadfast Noon’, at Ghedi and Aviano air bases in Italy. The drill allows NATO members to practise use of the B61 nuclear bombs stationed in Europe. According to NATO, aircraft and personnel from 14 unnamed NATO states took part. However, plane spotters only identified aircraft from the seven mentioned above, in addition to the United States. The host states practised loading and dropping of inert nuclear bombs with their dual-capable aircraft, and Czechia and Poland likely practised air-cover manoeuvres using conventional fighter aircraft.
More broadly, participation by non-nuclear-armed states in nuclear strike exercises, when conducted in especially sensitive circumstances of tension or conflict, may also amount to prohibited assistance with threatening to use nuclear weapons (Article 1(1)(d)), provided that it acted with knowledge and that its participation was a significant contribution. (See the section above on the prohibition on threatening to use.)
Several non-nuclear-armed states routinely commit conventional fighter planes or other military capabilities to joint manoeuvres with US or Russian strategic bombers. The dual capability of strategic bombers renders unequivocal legal assessment of such participation difficult. Provided that the manoeuvres in question are not specifically ‘nuclear’, i.e. that the deployed strategic bombers are not practising for the use of nuclear weapons but are instead involved in conventional-weapon roles, participation by non-nuclear-armed states is not controversial under the TPNW. That said, the deployment of strategic bombers often has a clear nuclear signalling effect. In most cases, however, information about the true nature of such manoeuvres (and the roles of the various non-nuclear-armed states involved) is not available.
The year 2021 saw a number of joint manoeuvres that, in the absence of further information, cannot be said straightforwardly to contravene the prohibition in Article 1(1)(e) of the TPNW, but which nevertheless cast nuclear shadows over the participation of non-nuclear-armed states. On 17 May 2021, for example, F-16 fighters from Bodø Air Base in Norway conducted manoeuvres with an American B-52 strategic bomber just south of the Arctic circle. The Norwegian warplanes were reportedly engaged as ‘joint terminal attack controllers’, meaning they were practising close air support and other offensive air operations from a forward position.
Probably the closest example in 2021 to a joint manoeuvre (beyond the nuclear strike exercises discussed above) where participation might be incompatible with Article 1(1)(e) of the TPNW was when Russian nuclear bombers, flanked by Belarusian fighter jets, flew patrols over Belarus in November. The patrols were carried out amid a dispute between Belarus and the European Union concerning migration at the Polish–Belarusian border. The Belarusian President, Alexander Lukashenko, said: ‘Let them scream and squeak. Yes, those are nuclear-capable bombers, but we have no other choice.'
B) Logistical and technical support
The provision of logistical and technical support to, for instance, a submarine specifically designed to carry nuclear weapons, would likely constitute assistance with possession of the weapons, provided that the support is a significant contribution. Port visits by SSBNs are rare, however, as such submarines typically seek to remain undetected and untraceable while on patrol. In June 2021, a US SSBN visited the UK Naval Base in Gibraltar in what was termed an ‘exceedingly rare’ stopover.
In the case of logistical and technical support for dual-use delivery vehicles, such as B-52 bombers or F-35 fighter-bombers, there will normally be no presumption of nuclear involvement. It will therefore be generally unproblematic for states parties to the TPNW that are allies and partners of nuclear-armed states to continue to host or provide logistical and technical support to those states’ dual-use delivery vehicles. In 2021, for instance, multiple US B-52s were hosted at Al Udeid Air Base in Qatar. B-52s were also hosted at the Morón Air Base in Spain. There is no evidence that the aircraft in question were specifically engaged or deployed in nuclear roles. If the purpose of a mission or presence with a nuclear-armed state’s dual-use delivery vehicle is clearly nuclear, however, the provision of logistical and technical support is likely to contravene the prohibition on assistance to and encouragement of prohibited activities.
The five nuclear host states provide logistical and security services at the bases where US nuclear weapons are deployed to their territory. This constitutes assistance with possession and stockpiling. (Of course, these five states are also acting in conflict with Article 1(1)(g), which explicitly prohibits the hosting of another state’s nuclear weapons.)
C) Intelligence gathering and sharing
If a state party to the TPNW were to engage in intelligence gathering and share it with a nuclear-armed state to knowingly identify targets for a temporally proximate use or threat to use nuclear weapons, this would amount to assisting use or threatening to use nuclear weapons.
A concrete case in point is Pine Gap, an intelligence facility built and funded by the United States outside Alice Springs in Australia and operated by the US National Reconnaissance Office. More than 800 Australian and US personnel staff the facility, including members of units from all four branches of the US military. One of the components of the facility is a Relay Ground Station in Pine Gap’s western compound, whose Overhead Persistent Infra-Red (OPIR) sensors will detect the heat bloom of any ICBMs or SLBMs launched against the United States. It provides early warning of an incoming attack but also indicates whether a nuclear missile launch site/launcher is empty (following firing) or not.
If Australia were to adhere to the TPNW and the Relay Ground Station were nevertheless used to identify imminent targets for US nuclear weapons, this would violate the prohibition on assisting use or the threatening of use. (This would not be the case if the data were used to identify targets for conventional strikes or to alert a vulnerable target population.) Since such future use or threat to use nuclear weapons remains a theoretical possibility, the operations of the Relay Ground Station do not presently constitute assistance or encouragement to use or threaten to use nuclear weapons.
In so far as it applies to nuclear weapons, however, the current arrangement with the Australian government at Pine Gap is part of the United States’ nuclear-strategic infrastructure and can thus be considered a manifestation of Australia’s encouragement of continued US possession of such weapons. Maintaining a capability and preparedness to identify targets for nuclear strikes also runs counter to the object and purpose of the TPNW. To ensure compatibility with the TPNW, Australia would therefore have to take the necessary action to provide assurances that the Relay Ground Station’s OPIR systems will not be used for nuclear targeting.
D) Participation in nuclear planning
Participation in nuclear strike planning entails an endorsement of the potential use of nuclear weapons in the future and, by extension, an encouragement of the possession and development of nuclear weapons in the present. Participation in planning of temporally proximate use or threats to use nuclear weapons would amount to assistance with use or the threatening of use. As discussed above, Australia was involved in nuclear planning and preparations in 2021 through its participation in the US nuclear command and control exercise Global Thunder, in contravention of Article 1(1)(e) of the TPNW.
From this perspective, participation in NATO’s Nuclear Planning Group (NPG) — the alliance’s senior body on nuclear strategy — is not compatible with Article 1(1)(e) of the TPNW. In the view of the Nuclear Weapons Ban Monitor, however, the TPNW does not necessarily preclude continued membership and participation in the NPG. The decisive criterion would be what happened inside the group. A state party to the TPNW could, for example, use its participation in the NPG only to promote nuclear disarmament.
Japan and South Korea on their part are engaged in ‘extended deterrence dialogues’ with the United States. To the extent that such dialogue is on general nuclear deterrence where future use is theoretical, their participation should be considered as encouragement of possession. To the extent that the dialogue concerns specific targets and is directed and communicated towards a specific adversary, it could also amount to assistance to threatening to use nuclear weapons. Any assessment is largely context-dependent. Thus, if Japan and South Korea were to adhere to the TPNW in the future, they would have to provide assurances that their respective ‘extended deterrence dialogues’ with the United States would not involve nuclear strike planning or target selection
E) Allowing the testing of missiles designed to carry nuclear warheads
Permitting the testing of missiles designed to carry nuclear warheads on one’s territory is not consistent with the TPNW’s prohibition on assistance with development of nuclear weapons. Two states (Kazakhstan, which is a state party, and the Marshall Islands, which is undecided on the TPNW) host test sites that have regularly served as the destination point for long-range missile tests carried out by Russia and the United States, respectively. In Kazakhstan, the site in question is the Sary-Shagan test site, a missile range established by the Soviet government in 1956. In the Marshall Islands, the site in question is the Ronald Reagan range at Kwajalein Atoll, a military station established after the Second World War. In both cases, the land on which the site is located is leased to the respective nuclear-armed state through long-term agreements. It is not the testing sites in and of themselves that conflict with the TPNW, but Russia’s and the United States’ use of them to maintain and develop nuclear-weapon missile technology.
The Reagan Test Site at Kwajalein Atoll was the destination point for at least two US ICBM tests in 2021. Should the Marshall Islands decide to adhere to the TPNW, such testing would need to stop if it involved nuclear-capable missiles. Marshallese adherence to the TPNW could thus lead to friction with the United States, perhaps helping to explain the Marshall Islands’ hesitancy about joining the Treaty. With its long history as a testing ground for US nuclear weapons, the Marshall Islands has been a strong supporter of nuclear disarmament and the campaign to end nuclear testing.
With respect to Kazakhstan, there is no evidence that Russia used the Sary-Shagan site to test missiles designed to carry nuclear warheads in 2021. Sary-Shagan appears not to have been used as the destination point for ICBM tests for some time now, possibly in reaction to Kazakhstan’s ratification of the TPNW. In fact, Russian officials have recently noted the problem of not having testing grounds on Russian soil, and Russia has reportedly begun constructing a new missile test site on Russian territory. (See: H. M. Kristensen and M. Korda, ‘Russian nuclear weapons, 2021’, Bulletin of the Atomic Scientists, Vol. 77, No. 2 (2021)). As a state committed to the goals of the TPNW, Kazakhstan should communicate its priorities to Russia and request that it continues to abstain from using the Sary-Shagan site for testing any missiles that can carry nuclear warheads.
It will be necessary to discuss these and other difficult compliance questions in a transparent manner, including at the TPNW’s meetings of states parties. Compliance and adherence will continue to build the norms established by the TPNW, and compliance issues arise in the implementation of almost every disarmament treaty. Kazakhstan, a nation that once inherited more than a thousand Soviet nuclear weapons and voluntarily relinquished them, is a long-time advocate of a world free of nuclear weapons. Together with its Central Asian neighbour-states, Kazakhstan established the Central-Asian NWFZ Treaty, which similarly obligates its member states not to ‘assist’ the development or manufacture of nuclear weapons.
It has been suggested that the obligation in TPNW Article 4(2) to ensure ‘the elimination or irreversible conversion of all nuclear-weapons-related facilities’ obligates Kazakhstan to close the Sary-Shagan site. However, Article 4(2) applies to any state that ‘owns, possesses or controls nuclear weapons or other nuclear explosive devices’ and can therefore not be applied to Kazakhstan. To the extent that Sary-Shagan is ‘clearly connected to Russia’s nuclear weapon complex’, any responsibility to eliminate or irreversibly convert the Sary-Shagan test site under Article 4(2) would fall on Russia.
F) Endorsement of nuclear-weapons doctrines, policies, and statements
All of NATO’s member states (the 27 umbrella states and the 3 nuclear-armed states) contravene Article 1(1)(e) of the TPNW through specific nuclear-related doctrines, policies, and/or statements to which they subscribe. NATO’s foundational document, the North Atlantic Treaty, does not mention nuclear weapons, but every NATO member has supported possession and potential use of nuclear weapons through their endorsement of various other alliance documents, particularly the Strategic Concept. None of the alliance’s members has so far rejected the possession or use, or even the first use, of nuclear weapons on its behalf. In the view of the Nuclear Weapons Ban Monitor, their endorsement of the Strategic Concept amounts to encouragement of possession of nuclear weapons. It does not, however, amount to encouragement of use, as that would require, for instance, a request for use of nuclear weapons in a specific context, or agreeing to rules of engagement allowing the use of nuclear weapons in a concrete multinational operation.
Three non-NATO US allies (Australia, Japan, and South Korea) also encourage possession of nuclear weapons through explicit statements they have made or strategy documents they have endorsed. For example, the governments of the United States and Japan expressed through a joint statement in 2013 that they remained committed to the security of Japan ‘through the full range of US military capabilities, including nuclear and conventional’. South Korea has endorsed similar statements with respect to its own position. In 2016, Japan and South Korea (together with France and the United Kingdom) reportedly expressed opposition to the Obama administration’s plans of adopting a nuclear no-first-use policy.
In addition to NATO, the Russian-led Collective Security Treaty Organization (CSTO) is understood by some observers as a ‘nuclear alliance’. In 2010, the CSTO’s Secretary-General suggested Russia had extended a ‘nuclear umbrella’ over all members of the alliance. Yet, CSTO members do not appear to have adopted official documents stipulating a nuclear dimension to the alliance. On the contrary, three members have actively distanced themselves from nuclear deterrence. Through the 2006 Treaty of Semipalatinsk — the treaty establishing Central Asia as an NWFZ — Kazakhstan, Kyrgyzstan, and Tajikistan have committed never to ‘assist or encourage’ the development, manufacture, or possession of nuclear weapons. Kazakhstan is also a state party to the TPNW.
Belarus, however, which is allied to Russia through the CSTO and the Union State, has on multiple occasions expressed support for nuclear deterrence, and its conduct is therefore not compatible with the TPNW’s prohibition on encouragement of possession of nuclear weapons. Armenia, the last CSTO member, has, to the Nuclear Weapons Ban Monitor’s knowledge, not explicitly endorsed the possession and potential use of nuclear weapons on its behalf. Armenia would, though, need to actively distance itself from nuclear deterrence in order to be considered compliant with Article 1(1)(e) of the TPNW, as fellow CSTO members Kazakhstan, Kyrgyzstan, and Tajikistan have already done through their adherence to the Treaty of Semipalatinsk, and in Kazakhstan’s case also to the TPNW.
For an overview of arrangements of extended nuclear deterrence (‘nuclear umbrellas’), see the table below.
In the United Kingdom, the government’s push for a full replacement of the Vanguard-class SSBNs in 2016 was based on the argument that NATO was a ‘nuclear alliance’ and that the United Kingdom thereby had no choice but to renew its arsenal of weapons of mass destruction.
In France, President Emmanuel Macron has recently re- launched the idea of a ‘European’ nuclear posture enacted by Paris. Specifically, the President has invited interested European states to take part in a dialogue about the French nuclear arsenal’s supposed contribution to European security. Similar initiatives have been made by most French governments since the 1960s, albeit with few takers and little enthusiasm among other European states.
Arrangements of extended nuclear deterrence
France, United Kingdom, United States, and Albania, Belgium, Bulgaria, Canada, Croatia, Czechia, Denmark, Estonia, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Montenegro, Netherlands, North Macedonia, Portugal, Romania, Slovakia, Slovenia, Spain, Turkey (NATO).
Russia and Belarus (CSTO/Union State); Russia and Armenia (CSTO); United States and Australia (Australia, New Zealand, United States Security Treaty (ANZUS))*; United States and Japan (Treaty of Mutual Cooperation and Security between the United States and Japan (Anpo)); United States and South Korea (Mutual Defense Treaty).
* New Zealand was de facto excluded from ANZUS in the mid-1980s due to its anti-nuclear-weapon policies.
Alliance membership and the TPNW
• Non-nuclear-armed states may adhere to the TPNW and remain within an alliance with one or more nuclear-armed states as long as they explicitly distance themselves from specific statements or formulations in alliance documents that amount to encouragement of use or possession of nuclear arms.
• It could be argued that for example a NATO member may, without having to explicitly ‘override’ previous endorsement of extended nuclear deterrence, become compliant with the TPNW through the acts of signing and ratifying the Treaty. However, having adhered to the TPNW, such a state would be obliged to refrain from endorsing future NATO language supporting the retention and potential use of nuclear weapons. This could be done either by adjusting the current language or by the state clearly rejecting possession or use of nuclear weapons on its behalf, for instance through ‘footnotes’, an interpretive or declaratory statement, or other unequal means of signalling disagreement with any endorsement of the potential use or possession of nuclear weapons. Such footnotes or statements could be simple and for instance phrased as follows: ‘State X does not support the possession or use of nuclear weapons or other nuclear explosive devices on its behalf and will not assist the development, possession, acquisition, or use of such weapons or devices in any way.’
• NATO members are not obliged to endorse every line of alliance language. Indeed, there is a tradition of member states ‘footnoting’ or otherwise distancing themselves from specific statements in alliance documents.
G) Development, production, and maintenance of key components for nuclear weapons
Numerous private companies are engaged in work linked to nuclear weapons. Most defence contractors involved in the nuclear enterprise are headquartered in the nuclear-armed states. However, some have headquarters or divisions in non-nuclear-armed states. As a result, as discussed below, the conduct of non-nuclear-armed Belarus, Italy, Germany, and the Netherlands is not compatible with the prohibition on assisting development and manufacturing nuclear weapons because they allow companies that are incorporated or have headquarters or production facilities on their territory to be involved in the development of nuclear weapon systems.
The Belarusian company Minsk Automobile Plant is the only manufacturer of the mobile launchers for the Russian Topol-M ICBM.
The German-headquartered company Airbus Defence and Space is currently involved in the development and production of French nuclear weapons. This development takes place within the framework of the joint venture company MBDA, which produces France’s air-launched cruise missiles, and the joint venture company ArianeGroup, which is the lead contractor for both France’s M51 nuclear-tipped SLBMs and the next generation of nuclear-tipped air-launched cruise missiles. Airbus Defence and Space is a subdivision of Airbus, which is headquartered in the Netherlands. Since Airbus considers that the actions of its subsidiaries form part of the work of Airbus as a group entity, both Germany and the Netherlands may be understood to presently be engaged in activities prohibited under Article 1(1)(e) of the TPNW.
The Italian company Leonardo (formerly Finmeccanica) is also involved in the development and production of France’s current nuclear-tipped air- launched cruise missiles through the joint venture MBDA (with Airbus and BAE Systems).
Corporate and state responsibility
A company that develops, produces, or maintains key components (such as a ballistic missile) for a nuclear weapon or other nuclear explosive device, or which maintains nuclear weapons, would thereby engage the international responsibility of the state in which it is operating. Such a state party would be responsible for prohibited assistance under the TPNW (assistance to development, production, or possession, depending on the acts the company was performing).
Depending on the circumstances, a parent company can also be legally responsible for the acts of its subsidiaries. The general position in domestic law is that a parent company is not liable where its subsidiary acts unlawfully. However, jurisprudence has established a number of exceptions to this general principle, allowing the ‘veil of separate legal status […] to be pierced’.* Under international law, contravention of the provisions of a disarmament treaty or of customary disarmament law by a corporation would suffice to render the state or states responsible on whose territory that corporation committed the relevant act or acts.
In addition, any company that is engaged in a joint venture that develops or produces key components for a nuclear weapon or other nuclear explosive device could thereby be engaging in prohibited assistance even if it does not itself contribute materially to the nuclear- weapon development or production. This is so wherever a company establishes a new body corporate, and is holding shares in that company. Under international law, the states on the territory of which the participating and shareholding companies are incorporated and/or have their headquarters would be responsible for the acts of the joint venture where those do not comply with an internatioonal treaty or customary law on disarmament.
* C. Murray et al., The Law and Practice of International Trade, 12th Edn, Sweet & Maxwell, 2012, §28-009.
H) Nuclear cooperation arrangements
The United Kingdom and France are engaged in close cooperation on maintenance of nuclear stockpiles, which amounts to prohibited (mutual) assistance with possession and stockpiling under the TPNW. The two states’ cooperation on stockpiling is supported by the 2010 Teutates Treaty to develop technologies for safe and effective maintenance of both states’ nuclear stockpiles.
US–French cooperation is conducted under a 1961 Mutual Defense Agreement, which permits limited cooperation on the operation of nuclear-weapon systems. Later amendments have enabled enhanced cooperation, notably on issues of safety, security, and reliability.
As discussed above under the prohibitions on transfer and on receiving transfer or control of nuclear weapons or other nuclear explosive devices, the United Kingdom and the United States continue to engage in close cooperation on Trident II SLBMs. The nature of the cooperation also amounts to US assistance with the United Kingdom’s development of nuclear weapons.
I) Financing of prohibited activities
According to the 2021 Pax/ICAN Don’t Bank on the Bomb report ‘Perilous Profiteering’, the total amount of loans offered to companies involved in the production and maintenance of nuclear weapons increased in 2021 compared to the previous year. At the same time, the number of investors decreased. In 2021, the year the TPNW entered into force, as many as 127 financial institutions divested from companies involved in the nuclear-weapons business. This was a significant increase on previous years, suggesting the TPNW had a significant impact on the financial sector.
The TPNW does not explicitly prohibit the financing of nuclear-weapon programmes. However, the prohibition on assistance renders unlawful direct funding of any of the prohibited activities listed in other subparagraphs of Article 1(1). If, for instance, funding in the form of an earmarked loan or credit line is provided to a company for the development or maintenance of nuclear weapons, this is unlawful assistance with the development, production, and possession of nuclear weapons.
The prohibition on financing encompasses not only state funding, such as sovereign wealth funds, but also private banks and individuals, as discussed above in the subsection on corporate and state responsibility. The ordinary purchase of shares in a company involved in the development, production, or maintenance of nuclear arsenals is not per se an illegal act under the TPNW, although ownership could be assessed differently depending on the amount of shares purchased while divestment from such companies is a growing trend.
The development, production, and maintenance of nuclear weapons constitutes a multi-billion-dollar industry, with numerous large companies and universities profiting from, and lending their legitimacy to, the industrial effort. The TPNW does not explicitly prohibit financing of nuclear-weapon programmes. However, the prohibition on assistance renders unlawful direct funding of any of the prohibited activities listed in the other subparagraphs of Article 1(1). If, for instance, funding in the form of an earmarked loan or a credit line is provided to a company for the development or maintenance of nuclear weapons, this is unlawful assistance with the development or possession of nuclear weapons.
The prohibition on financing encompasses not only state funding, including sovereign funds, but also private banks and individuals, as discussed above in the subsection on corporate and state responsibility. The ordinary purchase of shares in a company involved in the development, production, or maintenance of nuclear arsenals is not per se an illegal act under the TPNW, although ownership could be assessed differently depending on the amount of shares purchased and divestment from such companies is a growing trend.
Cuba issued a declaration upon joining the TPNW, stating that ‘The financing of any activity prohibited to a State Party under this Treaty is also a prohibited activity according to the provisions of Article 1(e)’. The prohibition on assistance also appears in the CCM, where it is widely considered to prohibit financing.
f) Uranium mining and export
Under international law, mining and transfer of uranium is generally lawful, unless it is for the purpose of developing or assisting in the development of a nuclear explosive device. The peaceful use of nuclear energy is protected under Article IV of the NPT, and the Preamble to the TPNW confirms that nothing in the Treaty should be interpreted as affecting that right. A state may therefore extract uranium and either use the nuclear material itself or provide it to another state for peaceful purposes, as long as it is subject to Safeguards Agreements with the International Atomic Energy Agency (IAEA).
Under the TPNW, the provision of uranium to any other state is prohibited where it is not subject to appropriate Safeguards Agreements or if the state party transferring the uranium knows that the material in question will, or is likely to, be used to develop a nuclear weapon or other nuclear explosive device. Otherwise, states parties to the TPNW are permitted to transfer uranium, including to nuclear-armed states and states not party to the TPNW. Several states that mine and export uranium are states parties to the TPNW, including Kazakhstan, Namibia, and South Africa.
Under the NPT, the provision of uranium to any non-nuclear-weapon state is unlawful where it is not subject to appropriate Safeguards Agreements. The NPT does not directly address the legality of provision of uranium to the five nuclear-weapon states designated under that Treaty.
If a state exports uranium to a nuclear-armed state or any other state on the understanding that the uranium would be used exclusively for peaceful purposes, the exporting state could not be considered to be in violation of either the TPNW or the NPT if the importing state unexpectedly decided to use the uranium for weapons development instead. This would, though, be likely to affect the legality of future exports of uranium to that state.
When armed groups control areas of a state’s territory or when an armed conflict is ongoing, situations could occur where it would be difficult for the authorities of a state in which uranium deposits exist to effectively control all extraction and transfers. If a non-state actor in such a situation were to transfer uranium to an actor intending to develop a nuclear explosive device, the territorial state could not be considered to be in violation of either the TPNW or the NPT, provided that it has made all reasonable efforts to prevent such extraction and transfers. All reasonable efforts would include the adoption of national legislation and implementation of other practical measures, to secure as far as possible sites in which uranium is present or where stocks of uranium are held.