Irreversibility of Nuclear Disarmament

Irreversibility is considered to be one of the three pillars of nuclear disarmament—alongside verification and transparency. It has become a widely used and acknowledged term in nuclear disarmament without the many stakeholders in nuclear disarmament sharing a common understanding of the concept. Long-term monitoring and verification arrangements will be required to reduce the risk of re-armament. However, verification has a broader utility that underpins and strengthens irreversibility in a number of other ways.

While not a prerequisite for moving forward with disarmament, the importance of achieving a common interpretation of irreversibility, and examining the subject in all its technical, legal, political, economic and social aspects, is increasingly being recognised.

Key aspects that need consideration include: the goal and tasks of verification throughout the broader process of irreversible disarmament; the key challenges and trade-offs associated with using verification to support irreversibility; and the broader impact and contribution of verification on the disarmament process.

In 2011, VERTIC published a ground-breaking research report ‘Irreversibility in Nuclear Disarmament: Practical steps against nuclear rearmament’

VERTIC continues to explore and address the links between verification and irreversibility.

Recent and on-going activities

Understanding irreversibility in global nuclear politics (2022-2023)

VERTIC has been part of a consortium of leading universities and research centres, from the UK and beyond to understand irreversibility in global nuclear politics and to investigate the concept of ‘nuclear irreversibility’ in disarmament and arms control. The consortium consisted of King Collage London, the Centre for Strategy and International Studies (CSIS), the European Leadership Network (ELN), and the University of York.

The consortium sought to generate new conceptual insights that could aid a more informed understanding of nuclear irreversibility in the context of the NPT Review process and beyond. Within this project, VERTIC has also examined the role of IAEA Safeguards for irreversibility and besides for undertaking its own research, also commissioned a paper to address the links between irreversibility of nuclear disarmament and verification from an African perspective.


This work was funded by the Counter Proliferation and Arms Control Centre (CPACC) of the Foreign & Commonwealth Office, UK.

Framing Irreversibility as Management of Nuclear Latency (2022-2024)

VERTIC is currently undertaking a project with the Open Nuclear Network, One Earth Futures Austria that includes framing irreversibility through the lens of ‘latency’. This project aims to identify latency indicators and then match these indicators to inform the planning of long-term verification and monitoring measures. This includes developing a map of indicators of capability and intent that can be used to assess, plan and monitor irreversibility measures, across the areas of nuclear fuel cycle.


This work is funded by the Bureau of Arms Control, Verification and Compliance of the U.S. Department of State.

Practical considerations for irreversibility of nuclear disarmament (2023-2024)

Research and dialogue on the practical considerations of the irreversibility of nuclear disarmament to support discussions in the current review cycle of the NPT is also being implemented.

In this respect, VERTIC has, inter alia, partnered with Argentina-based NPSGlobal to host a workshop with diplomats, policy and technical experts from Latin America. The workshop aims to advance the irreversibility debate by eliciting regional or ‘Global South’ perspectives and in particular on the potential link between the peaceful use of nuclear energy and the proliferation of expertise for the development of nuclear weapons programmes. In this way, the workshop aims to gather both practical and conceptual inputs as a contribution to the wider conversation on irreversible nuclear disarmament.


This work is funded by the Counter Proliferation and Arms Control Centre (CPACC) of the Foreign & Commonwealth Office, UK.