Tonga
Tonga voted in favour of the 2024 and 2025 UN General Assembly resolutions on the Treaty on the Prohibition of Nuclear Weapons (TPNW), which welcomed the Treaty’s entry into force and called upon ‘all States that have not yet done so to sign, ratify, accept, approve or accede to the Treaty at the earliest possible date’.1 In previous years, it had abstained from voting. Tonga maintains policies and practices that are compatible with all of the prohibitions in Article 1 of the Treaty, and can therefore sign and ratify it without the need for a change in conduct.
TPNW Status
| Key weapons of mass destruction treaties | ||
|---|---|---|
| NUCLEAR WEAPONS | ||
| Party to the TPNW | No | |
| Party to the NPT | Yes (Acceded 1971) | |
| Ratified the CTBT | No | |
| Party to an NWFZ | Yes (Ratified 1996, Rarotonga) | |
| CSA with the IAEA | Yes (In force 1993) | |
| AP with the IAEA | No | |
| BIOLOGICAL AND CHEMICAL WEAPONS | ||
| Party to the BWC | Yes (Acceded 1976) | |
| Party to the CWC | Yes (Acceded 2003) | |
| 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 | Compatible |
| (f) | Seek or receive assistance | Compatible |
| (g) | Allow stationing, installation, deployment | Compatible |
| TPNW voting and participation | |
|---|---|
| UNGA resolution on TPNW (latest vote) | Voted yes (2025) |
| Participated in 3MSP (2025) | No |
| Participated in 2MSP (2023) | No |
| Participated in 1MSP (2022) | No |
| Average MSP delegation size (% women) | N/A |
| Adoption of TPNW (7 July 2017) | Voted yes |
| Participated in TPNW negotiations (2017) | Yes |
| Negotiation mandate (A/RES/71/258) | Voted yes |
| Fissile material | |
|---|---|
| Nuclear facilities | No |
| Fissile material production | No |
| HEU stocks | No |
| Plutonium stocks | No |
| SQP with the IAEA | Yes (Revised) |
Latest developments
At the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) Preparatory Committee meeting in April 2025, Tonga delivered a statement on behalf of the States Parties to the South Pacific Nuclear Free Zone Treaty reaffirming their commitment to a nuclear-weapon-free world. ‘As a region devastatingly affected by nuclear testing, the slow pace of nuclear disarmament is a significant concern,’ the States Parties said.2
At a high-level event on 26 September 2025 marking the International Day for the Total Elimination of Nuclear Weapons, the Pacific Islands Forum, of which Tonga is a member State, noted the ‘significant contribution’ of the 1985 South Pacific Nuclear Free Zone Treaty to nuclear non-proliferation and disarmament and to ‘inspiring other nuclear-weapon-free zones around the world’.3
Recommendations
-
Tonga should urgently adhere to the TPNW.
-
Tonga should conclude and bring into force an Additional Protocol (AP) with the International Atomic Energy Agency (IAEA).
-
Tonga should adhere to the Comprehensive Nuclear-Test-Ban Treaty (CTBT).