As of 19 September 2023, the TPNW has 69 states parties while 28 further states have signed but not yet ratified. This means that a total of 97 states (or 49.2% of all states) have accepted binding obligations in international law under the TPNW. Only 2 more signatures or accessions are needed to pass 50%.
Of the 100 states that are not yet states parties or signatories to the TPNW, 42 states are identified by the Nuclear Weapons Ban Monitor as ‘other supporters’ on the basis of their most recent voting record on the Treaty in the UN General Assembly. As illustrated in the animation above, this means that a total of 139 states (more than 70% of the global total of 197 states) are supportive of the TPNW, while 43 states (almost 22%) are opposed, and 15 states (almost 8%) are undecided. The criteria for the Ban Monitor’s categorisation of states by their position on the TPNW are explained in the table below. For details about individual states, see the state profiles on this website.
States parties and signatories
The nine states that ratified the TPNW in 2022 were Cabo Verde, Congo, Côte d’Ivoire, the Democratic Republic of the Congo, the Dominican Republic, Grenada, Guatemala, Malawi, and Timor-Leste, and the new signatories were Barbados, Burkina Faso, Equatorial Guinea, Haiti, and Sierra Leone. Djibouti signed the TPNW on 9 January 2023.
Of the 69 states that as of 19 September 2023 were parties to the TPNW, four—the Cook Islands, Mongolia, Niue, and Sri Lanka—had acceded to the Treaty while the remainder had signed and ratified it. In several of the 28 states that were signatory states, the executive branch of government had submitted the TPNW to the legislature for review and approval for ratification. These included Brazil, Equatorial Guinea, and Indonesia.
Of the combined total of 97 states parties and signatories as of 19 September 2023, 82 were among the 122 states that negotiated and adopted the TPNW at the diplomatic conference in the UN in June–July 2017. Of the adopting states, therefore, 66% had by the end of 2022 proceeded to become either a state party or at least a signatory. In addition, 13 states that did not take part in the Treaty adoption in 2017 had also become a state party or a signatory.
While they have not yet signed or adhered to the Treaty, the states in the group of other supporters have expressed their support to the TPNW by voting in favour—and in some cases also co-sponsoring—the annual UN General Assembly resolution on the TPNW. The resolution calls upon all states that have not yet done so to sign, ratify, or accede to the Treaty ‘at the earliest possible date’.
Several of the other supporters have already started domestic processes to sign or accede to the TPNW. These include Eritrea, Eswatini, Mauritania, Papua New Guinea, Solomon Islands, and Uganda. Six of the other supporters (Iraq, Mauritania, Morocco, Qatar, Senegal, and Yemen) participated as observers at the First Meeting of States Parties to the TPNW in 2022.5
Most of the states in this category were among the 122 states that adopted the TPNW in July 2017, but it also includes a total of ten states that did not take part in the adoption of the TPNW in 2017, but which have subsequently expressed their support for the Treaty by voting in favour of the annual UN General Assembly resolution.
As mentioned above, less than 8% of the global total of states are undecided on the TPNW. This mixed group of 15 states is spread out across all five continents, and now includes three umbrella states. Armenia and Belarus—the only states with arrangements of extended nuclear ‘deterrence’ with Russia—have abstained on all the annual UN General Assembly resolutions on the TPNW since it was initiated in 2018, including in 2022. That year, Australia became the first umbrella state allied to the United States to abstain rather than vote against the UN General Assembly resolution on the TPNW. Ahead of the vote, the Australian government indicated that it is assessing its position on the TPNW, ‘taking account of the need to ensure an effective verification and enforcement architecture, interaction of the Treaty with the Nuclear Non-Proliferation Treaty (NPT) and achieving universal support’. The Australian Labor Party, which formed the new government in May 2022 after a general election, adopted a resolution in 2018 committing it to sign and ratify the TPNW in government, after taking account of the above-mentioned factors.
The category of undecided states also includes five states that voted to adopt the TPNW in 2017 but which have not yet proceeded to adhere to the Treaty: Argentina, the Marshall Islands, Saudi Arabia, Switzerland, and Tonga. Saudi Arabia’s commitment to nuclear non-proliferation has been open to question in recent years. Argentina, the Marshall Islands, and Switzerland are in protracted processes to arrive at a final national position on the TPNW.
Argentina stated in 2022 that it has ‘initiated an analysis and review process of the [TPNW] that has not yet been completed’. In announcing its decision to participate as an observer at the First Meeting of States Parties to the TPNW in 2022, the Marshall Islands—a state severely impacted by nuclear-weapons testing—said that it wanted ‘to see what concrete victim assistance provisions actually come forward by states parties and if they are at scale’.
In November 2022, 34 prominent Swiss citizens, including former government officials, federal councillors, and presidents and vice-presidents of the International Committee of the Red Cross, criticised the government’s decision not to sign the TPNW to date as an ‘unjustifiable anomaly’ and called on it to become a signatory immediately. Both houses of the Swiss Parliament have previously instructed the government to proceed with signature and ratification of the TPNW without delay. Switzerland’s highest executive authority, the Federal Council, intended to decide in ‘early’ 2023 whether or not Switzerland will become a state party to the TPNW based on a report to be published by the federal administration. At the time of writing, no decision had been announced.
The group of states opposed to the TPNW increased from 42 to 43 in the course of 2022. As discussed above, Australia ended its opposition to the Treaty, while 29 of the 30 umbrella states that are allies of the United States remained opposed to the TPNW, along with all nine nuclear-armed states. In addition, Sweden and Finland rejected the TPNW and voted no on the UN General Assembly resolution on the TPNW instead of abstaining as in previous years, following their applications for NATO membership. Finally, three states with nuclear-free defence postures but with close ties to nuclear-armed states—Bosnia and Herzegovina, Micronesia, and Monaco—continued to vote against the resolution. In several opposed states, however, political debate about adherence to the TPNW continued in 2022. NATO states Belgium, Germany, the Netherlands, and Norway participated as observers at the TPNW’s First Meeting of States Parties in June, in the face of strong pressure from the United States and from NATO Secretary-General Jens Stoltenberg not to do so. Also NATO applicants Finland and Sweden participated as observers. Japan opted not to attend as an observer, generating anger and disappointment among atomic bomb survivors.
Regional distribution of support
Breaking down all states’ positions on the TPNW by region, the figure and maps below show that support for the TPNW is high in all regions of the world apart from Europe. As of 31 December 2022, all states in Africa now formally support the Treaty, either as states parties or signatories, or as other supporters.
Africa is followed by the Americas, where all but three states are either states parties, signatories, or other supporters, with only Argentina remaining undecided and the United States and Canada opposed. The Americas is also the region with the highest share of states parties, with 26 states parties (or over 74%) among the regional total of 35 states by the end of 2022. With Guatemala’s ratification of the TPNW in June 2022, Central America became the first entire subregion where all states are party to the Treaty. The Caribbean Community (CARICOM) also announced in October that all of its member states are now ‘either parties, signatories or in [the] process of acceding to the TPNW’.
In Oceania, too, the share of states parties is high, with 10 states parties (62%) among the 16 states in the region. Micronesia is now the only opposed state in this region, while Australia, the Marshall Islands, and Tonga are undecided. In Asia, the five nuclear-armed states located in this region (China, India, Israel, North Korea, and Pakistan) were opposed to the TPNW in 2022, together with US umbrella states Japan and the Republic of Korea (South Korea). Support for the TPNW, however, is relatively high also in Asia. A total of 32 of 45 states in the region (71%) are states parties, signatories, or other supporters.
Europe continues to be the region with the highest concentration of opposed states. A total of 33 of the 47 states (70%) in Europe were opposed to the TPNW in 2022. The region has only five states parties: Austria, Holy See, Ireland, Malta, and San Marino; and one signatory that has not yet ratified: Liechtenstein.
Speed of adherence across WMD treaties
The TPNW is the youngest Treaty in the broader legal architecture for disarmament and non-proliferation of weapons of mass destruction (WMD). As mentioned above, nine states ratified and five states signed the TPNW in 2022. The animation below shows the speed of ratification and accession of the TPNW relative to the other WMD treaties. In its first years, the TPNW’s speed of ratification and accession was on average the same as for the other WMD treaties, despite obstructionism from nuclear-armed states. During the course of 2021—the second year of the COVID pandemic—the TPNW fell behind the other treaties. It then picked up more speed again in 2022 and was not far behind the levels of ratification and accession levels of the Biological Weapons Convention (BWC) and the Treaty on the Non-Proliferation of Nuclear Weapons (NPT).
The patterns of ratifications/accessions for the BWC and NPT serve as a timely reminder that it took several years also for those treaties to accrue authority. Just over five years and three months (63 months) after opening for signature, the TPNW had, as mentioned above, attracted 68 ratifications and accessions. Over the same period of time following opening for signature, the BWC had obtained 71 ratifications and accessions, the NPT 76, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) 89, and the Chemical Weapons Convention (CWC) 107 ratifications and accessions.
Level of adherence across WMD treaties
Some treaties allow only UN member states to adhere (the obvious example being the UN Charter), but most treaties—including all of the above-mentioned treaties in the legal architecture for disarmament and nonproliferation of WMD—use the ‘all states’ formula. This currently allows a total of 197 states to adhere: the 193 UN Member States, the two UN observer states (Holy See and the State of Palestine), as well as the two other states (Cook Islands and Niue). The objective must be universal adherence to all of the components in this architecture, meaning that all 197 states should be states parties to each and every one of them. The figure below therefore highlights the gaps in adherence as of 31 December 2022, across all the treaties. Where a state is not yet a state party to any of these five treaties, this is noted in its respective state profile on this website, along with a recommendation for urgent adherence.
The most ratified WMD treaty is the CWC, to which 193 states are party. Of the four states that have not yet adhered to this Treaty, one is a signatory. The NPT has five outliers, the BWC had four signatories and 9 outliers at the end of 2022, and the CTBT 11 signatories and 11 outliers.As discussed above, as of the end of 2022, there were in total 103 states that were not yet states parties or at least signatories to the TPNW.
Two states (Israel and South Sudan) are outliers on all of the five treaties; two states (Egypt and North Korea) are outliers on four; and four states (India, Pakistan, Somalia, and Syria) are outliers on three treaties.
In building upon and contributing to the other WMD treaties, the TPNW has the potential to reinforce the legitimacy of the legal WMD architecture as a whole. In 2022, the CTBT gained six new states parties (Dominica, Equatorial Guinea, Gambia, Sao Tome and Principe, Timor-Leste, and Tuvalu), and the BWC one new state party (Namibia). All of this progress took place in states that were already states parties or signatories to the TPNW, apart from Equatorial Guinea, which ratified the CTBT the day before it signed the TPNW in September 2022. For the CWC, the latest development was Palestine’s accession in 2018. Palestine was also the most recent country to adhere to the NPT, in 2015