Highlight 39/2025: The Importance of Non-Proliferation of Nuclear Weapons (NPT), Indonesia’s Advocacy for Universal and Binding Negative Security Assurances

Rina Permatasari, 17 September 2025

In an increasingly unstable geopolitical climate, the need for legally binding negative security assurances (NSAs) has become more pressing. Heightened tensions among nuclear-armed states and the erosion of multilateralism threaten the credibility of the global non-proliferation regime. The lack of binding NSAs undermines the trust underpinning the Treaty on the Non-Proliferation of Nuclear Weapons (NPT).

Indonesia, a steadfast non-nuclear-weapon state and disarmament advocate, considers legally binding NSAs vital to rectifying the structural imbalance within the NPT. For Indonesia, NSAs are not merely diplomatic gestures but essential legal guarantees that enhance stability in a volatile international environment. The absence of such assurances weakens the rationale for non-nuclear status, particularly in sensitive regions, potentially encouraging nuclear proliferation under the pretext of self-defence.

This concern has been echoed repeatedly in international forums, including the Conference on Disarmament (CD), where NSAs have been a topic of discussion since the 1960s, through United Nations General Assembly Resolution 21/53(a) (1966). In addition to the resolution, the international community has long acknowledged the importance of NSAs, through the Final Document of the First Special Session on Disarmament (SSOD-I) and the Action Plan adopted at the 2010 NPT Review Conference which call for legally binding NSAs for Non-Nuclear Weapon States (NNWS). However, despite these commitments, little progress has been made.

Indonesia’s efforts to revive discussions demonstrate continued dedication in geopolitical tensions, especially during Indonesia’s presidency at Conference of Disarmament from February to March 2024.  In regional’s framework, Indonesia’s pursuit of NSAs is also deeply intertwined with its leadership role and its commitment to the Southeast Asia Nuclear Weapon-Free Zone (SEANWFZ) or Treaty of Bangkok. Indonesia recognizes the value of existing assurances provided by nuclear-weapon states (NWS), also known as the P5 in the United Nations Security Council (UNSC), such as those found in Nuclear-Weapon-Free Zone treaties, including the SEANWFZ. However, it maintains that these assurances are inadequate due to their conditional, non-binding, or geographically limited nature.

In 2023, Indonesia submitted a Working Paper titled Effective International Arrangements to Assure Non-Nuclear-Weapon States Against the Use or Threat of Use of Nuclear Weapons to CD Forum emphasizing the importance of sustained dialogue between ASEAN and the NWS to encourage the latter’s accession to the Protocol of the SEANWFZ Treaty during the 2023 Indonesia’s ASEAN Chairmanship and further.

The accession of the  NWS to the Protocol holds profound significance, as it would constitute a legally binding commitment not to use or threaten to use nuclear weapons within the Zone. Such a commitment would not only affirm the P5’s support for the principles of the global nuclear non-proliferation regime, particularly the Treaty on the NPT, but would also enhance the credibility of nuclear-weapon-free zones as instruments of regional stability and global disarmament.

Ultimately, Indonesia contends that legally binding NSAs are essential to fulfilling the promise of the NPT. Such guarantees would provide NNWS with confidence and reinforce the global disarmament and non-proliferation regime. In conclusion, while the total elimination of nuclear weapons remains the most effective assurance against their use, the establishment of a universal, unconditional, and legally binding NSA framework is an urgent necessity for global peace and security.

Rina Permatasari, Highlight 39/2025: The Importance of Non-Proliferation of Nuclear Weapons (NPT), Indonesia’s Advocacy for Universal and Binding Negative Security Assurances, 17 September 2025, available at www.meig.ch

The views expressed in the MEIG Highlights are personal to the authors and neither reflect the positions of the MEIG Programme nor those of the University of Geneva.