Finland
Following Finland’s accession to NATO in 2023, the Finnish government outlined its position on the Treaty on the Prohibition of Nuclear Weapons (TPNW) in a statement to parliament. ‘The [TPNW] is incompatible with our NATO membership,’ it said. ‘The TPNW would weaken our influence in the alliance and could be interpreted as a lack of solidarity.’1 Finland may sign and ratify or accede to the TPNW, but will have to make changes to its policies and practices to become compliant.
TPNW Status
| Key weapons of mass destruction treaties | ||
|---|---|---|
| NUCLEAR WEAPONS | ||
| Party to the TPNW | No | |
| Party to the NPT | Yes (Ratified 1969) | |
| Ratified the CTBT | Yes (Ratified 1999, Annex 2 state) | |
| Party to an NWFZ | No | |
| CSA with the IAEA | Yes (In force 1981) | |
| AP with the IAEA | Yes (In force 2004) | |
| BIOLOGICAL AND CHEMICAL WEAPONS | ||
| Party to the BWC | Yes (Ratified 1974) | |
| Party to the CWC | Yes (Ratified 1995) | |
| TPNW Art. 1(1) prohibitions: Compatibility in 2025 | ||
|---|---|---|
| (a) | Develop, produce, manufacture, acquire | Compatible |
| Possess or stockpile | Compatible | |
| Test | Compatible | |
| (b) | Transfer | Compatible |
| (c) | Receive transfer or control | Compatible |
| (d) | Use | Compatible |
| Threaten to use | Compatible | |
| (e) | Assist, encourage or induce | Non-compatible |
| (f) | Seek or receive assistance | Compatible |
| (g) | Allow stationing, installation, deployment | Compatible |
| TPNW voting and participation | |
|---|---|
| UNGA resolution on TPNW (latest vote) | Voted no (2025) |
| Participated in 3MSP (2025) | No |
| Participated in 2MSP (2023) | No |
| Participated in 1MSP (2022) | Yes (observer) |
| Average MSP delegation size (% women) | 3 (33%) |
| Adoption of TPNW (7 July 2017) | N/A |
| Participated in TPNW negotiations (2017) | No |
| Negotiation mandate (A/RES/71/258) | Abstained |
| Fissile material | |
|---|---|
| Nuclear facilities | Yes |
| Fissile material production | No |
| HEU stocks | No |
| Plutonium stocks | No |
| SQP with the IAEA | No |
Latest developments
In March 2026, the Finnish government announced plans to lift the country’s long-standing ban on having nuclear weapons on its territory. The Defence Minister, Antti Häkkänen, said that the government’s proposed legislative changes would make it possible to ‘bring a nuclear weapon into Finland, or to transport, deliver, or possess one in Finland, if it is connected to the military defence of Finland’. He described the changes as ‘necessary to enable Finland’s military defence as part of the [NATO] alliance and to take full advantage of NATO’s deterrence and collective defence’.2
In the Conference on Disarmament in February 2025, Finland praised US President Donald Trump for his statements ‘calling for nuclear disarmament’ and said that there are ‘numerous reasons for leaders of the Russian Federation and China to take this opportunity to advance nuclear disarmament’.3
At the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) Preparatory Committee meeting in May 2025, Finland described nuclear disarmament as ‘a gradual process that requires proper attention to the legitimate security concerns of all participants’. ‘However, challenges and difficulties are no reason to halt nuclear disarmament efforts,’ it said.4
In the First Committee of the UN General Assembly in October 2025, Finland expressed concern that the ‘global arms control, disarmament, and non-proliferation architecture is under increasing strain’ and reiterated its support for the NPT, calling for its full and effective implementation.5
In March 2024, the President of Finland, Alexander Stubb, said ‘that we in Finland must have a real nuclear deterrent, and that’s what we have’ as a NATO member.6
In September 2024, the Finnish government said: ‘Finland actively promotes nuclear disarmament and the non-proliferation of weapons of mass destruction. NATO membership will not change Finland’s arms control and disarmament policy, which emphasizes the importance of agreements and of ensuring that the agreements are complied with and implemented.’7
Having observed the First Meeting of States Parties (1MSP) to the Treaty on the Prohibition of Nuclear Weapons (TPNW) in 2022, Finland opted not to observe subsequent meetings in 2023 and 2025. ‘NATO’s nuclear powers have criticized member countries that participated in the TPNW meeting in June 2022 and often recall the incompatibility of NATO membership and the TPNW,’ the government informed parliament.8
Recommendations
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Finland should renounce the possession and potential use of nuclear weapons on its behalf, and ensure that nuclear weapons do not have a role in its defence posture.
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Finland should comply with its existing obligation under Article VI of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and pursue negotiations in good faith on nuclear disarmament.
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Finland should urgently adhere to the TPNW. Until it is in a position to do so, it should welcome the TPNW as a valuable component in the global disarmament and non-proliferation architecture, work with the Treaty's states parties on practical steps towards disarmament, and attend the meetings of states parties as an observer.