The independent resource on global security

11. Nuclear disarmament, arms control and non-proliferation


Overview, Tytti Erästö, Vitaly Fedchenko and Petr Topychkanov

I. Russian–United States nuclear arms control and disarmament, Petr Topychkanov

II. Implementation of the Joint Comprehensive Plan of Action on Iran’s nuclear programme, Tytti Erästö

III. Multilateral nuclear arms control, disarmament and non-proliferation treaties and initiatives, Tytti Erästö, Shannon Kile and Vitaly Fedchenko

Treaty on the Prohibition of Nuclear Weapons enters into force

Although, on balance, 2020 was a difficult year for nuclear arms control and non-proliferation efforts, it witnessed a crucial milestone in the development of inter­national norms on nuclear disarmament: on 24 October 2020 Honduras became the 50th state to ratify or accede to the 2017 Treaty on the Prohibition of Nuclear Weapons (TPNW), triggering its entry into force 90 days later. The TPNW is the first treaty to establish a comprehensive ban on nuclear weapons, including their develop­ment, deployment, possession, use and threat of use. This prohibition, how­ever, has brought to the fore the tension between nuclear disarmament and nuclear deter­rence: while civil society and many non-nuclear weapon states welcomed the entry into force of the treaty, the nuclear weapon states (China, France, Russia, the United Kingdom and the United States) and their allies viewed it as undermining the existing nuclear order based on the 1968 Treaty on the Non-Proliferation of Nuclear Weapons (Non-Proliferation Treaty, NPT).


The Covid-19 pandemic led to the post­ponement of the 10th review conference of the NPT. It would have marked the 50th anniversary of the NPT’s entry into force, in 1970, and a quarter of a century since the treaty was indefinitely extended, in 1995. Many welcomed the postponement as the conference appeared set to fail in the political context that prevailed in 2020—a context shaped mainly by the long-standing failure to make progress on nuclear disarmament.


Russian–US nuclear arms control

In keeping with over a decade of diplomatic deadlock in bilateral nuclear arms control between Russia and the USA, little progress was made in their negotiations in 2020. In addition to the deterioration in general Russian–Western political and security relations, contemporary developments in military technology have also complicated strategic dynamics and contributed to this deadlock. Despite their efforts to address relevant issues in the Strategic Security Dialogue framework, by the end of 2020 Russia and the USA had still not agreed to extend their last-remaining bilateral nuclear arms control treaty, the 2010 Treaty on Measures for the Further Reduction and Limitation of Strategic Offensive Arms (New START), which was due to expire on 5 February 2021. The fate of New START remained in the balance due to the different approaches and goals of the two sides: Russia focused on preserving the treaty, while the USA sought to convince China—with no success—to join the agreement and to make it more compre­hensive in terms of the weapons covered and the verification measures imposed. 


Aggregate numbers of Russian and US strategic offensive arms under New Start


Iran and the Joint Comprehensive Plan of Action

The future of the 2015 Joint Comprehensive Plan of Action (JCPOA) also remained uncertain in 2020. The JCPOA is an agree­ment between Iran and six other participating states, as well as the European Union, designed to build international confidence about the exclusively peaceful nature of the Iranian nuclear programme in return for the lifting of sanctions. Iran remained a participant in the JCPOA in 2020, although it was no longer observing key provisions of the agreement. Iran had begun to exceed JCPOA limits on its nuclear activities in 2019 in response to the US ‘maximum pressure’ policy—which, following the US withdrawal from the JCPOA in 2018, included ever-harsher sanctions on Iran. Iran continued to maintain that it would return to full compliance as soon as the other parti­ci­pants did the same. The prospects for reviving this ailing nuclear agreement in 2021 were improved by the election of a new US president in late 2020. However, the window for Iran and the USA to agree on the terms for returning to their respec­tive JCPOA commitments remained narrow.


North Korea

Since the breakdown of the short-lived nuclear diplomacy between the USA and the Democratic People’s Republic of Korea (DPRK, or North Korea) in 2018–19 a stale­mate has ensued, and this continued throug­hout 2020. In January North Korea announced that it would no longer observe its unilateral moratoriums on nuclear test explosions and test flights of long-range ballistic missiles that it had declared in 2018. While it conducted no such tests during the year, it continued development of its shorter-range ballistic missiles. 


Controversies related to the Comprehensive Nuclear-Test-Ban Treaty 

The difficult political context for nuclear arms control was also apparent in relation to the 1996 Comprehensive Nuclear-Test-Ban Treaty (CTBT)—the international treaty that would ban all nuclear test explosions in all environments when it enters into force. In 2020 US officials reportedly discussed the option of conducting a so-called demonstration nuclear explosion, which would have been the first US nuclear explosive test since 1992. By the end of the year, given the adverse political reactions, the political changes in the USA after the elections in November, and various technical diffi­culties, such a test seemed unlikely. Mean­while, as in previous years, the USA questioned whether China and Russia were adhering to their unilateral testing morator­iums. Both denied the US assertions, which have not been sub­stantiated by publicly available evidence.