The TPNW is the first legally binding multilateral treaty to comprehensively ban nuclear weapons, though no nuclear-armed state has joined.
Key Facts
- Adopted
- 7 July 2017
- Opened for signature
- 20 September 2017
- Entered into force
- 22 January 2021
- Votes in favour
- 122
- Votes against
- 1 (Netherlands)
- Nuclear-armed states joined
- 0
By the Numbers
Location
Cause → Event → Consequence
The United Nations General Assembly adopted a mandate on 23 December 2016 to schedule formal negotiations on a nuclear weapons ban, responding to longstanding civil society and non-nuclear-state pressure for a legally binding instrument beyond existing non-proliferation frameworks.
Negotiations were held in two sessions in March and June–July 2017 at the UN. On 7 July 2017, the Treaty on the Prohibition of Nuclear Weapons was adopted with 122 votes in favour, 1 against, and 1 abstention, and was opened for signature on 20 September 2017.
The treaty entered into force on 22 January 2021, establishing binding prohibitions on development, testing, production, stockpiling, and use of nuclear weapons for signatory states. However, all nuclear-armed states and NATO members declined to join, limiting its practical disarmament impact.
Political Outcome
Treaty adopted with 122 votes in favour; entered into force 22 January 2021, but no nuclear-armed state has acceded.