VERTIC Senior Researcher Hugh Chalmers comments on the recent decision by the Russian Federation to revoke its ratification of the Comprehensive Nuclear Test Ban Treaty (CTBT).  

The Russian Federation has formally taken the decision to withdraw its ratification of the Comprehensive Nuclear Test Ban Treaty (CTBT). However, Russia remains a signatory to the treaty and has retained national legislation related to CTBT implementation.  

The CTBT was adopted by the UN General Assembly nearly 30 years ago but is not yet in force. The treaty prohibits States Parties from carrying out nuclear weapon test explosions, and deters non-compliance through a verification regime that comprises, among other things, an International Monitoring System (IMS) and on-site inspections. The IMS has largely already been established by the Comprehensive Nuclear Test Ban Treaty Organisation (CTBTO) Preparatory Commission and consists of over 300 monitoring stations located throughout the world. It has detected all six nuclear tests conducted by the DPRK. However, the Treaty itself – and key mechanisms such as on-site inspections – will only enter into force after all 44 of its ‘Annex 2’ States have ratified it.1 Of these 44, eight have not yet done so: China, Democratic People’s Republic of Korea, India, Pakistan, Iran, Israel and the United States of America.  

Russia deposited its instrument of ratification with the UN Secretary-General on 30 June 2000, having passed domestic legislation a month earlier ratifying the treaty and providing the basis for implementing its related obligations. However, Russia has now passed legislation repealing the first article of their CTBT law, thus withdrawing its ratification.  Russia has portrayed its actions as a response to the absence of US ratification but it is unlikely to encourage the US or other Annex 2 states to ratify the Treaty by distancing themselves from it.   

Russia has now passed legislation repealing the first article of their CTBT law, thus withdrawing its ratification. 

This also casts doubt on Russia’s commitment to the object and purpose of the CTBT. Russia has been a strong supporter of the CTBT since its inception: it hosts 32 IMS stations on its territory and plays a major role in the CTBTO. Russia continues to assert its support for the CTBTO, saying “We will transmit our [IMS] data, receive other people’s data. The [testing] moratorium remains in place. We’re just withdrawing ratification. That’s it.” However, the longevity, robustness, and breadth of that support is now questionable. Of particular concern are statements indicating a willingness to resume testing should the United States do so, ambiguity over prospects for testing new weapons, and reports of activities at test sites. The withdrawal of ratification also raises questions as to whether Russia, as an Annex 2 state itself, would have to re-ratify the Treaty for it to enter into force.2 

Russia’s withdrawal of ratification in the broader international law context 

Recalling the international legal framework surrounding the CTBT and Russia’s implementing measures could help provide some reassurance. As a signatory to the CTBT, Russia is still bound by a broader framework of international law that supports the treaty and preparations for its entry into force. The Vienna Convention on the Law of Treaties, which codifies customary international law, requires signatories to a treaty to “refrain from acts which would defeat the object and purpose” of that treaty prior to its entry into force.  States Signatories should remember their obligations in this regard under the Vienna Convention and customary international law.  

Recommendation: States Signatories to the CTBT should consider recalling their obligations arising from the Vienna Convention on the Law of Treaties and customary international law to refrain from acts which would defeat the object and purpose of the Treaty.

Russia is also bound by Resolution CTBT/MSS/RES/1 (November 1996), establishing the Preparatory Commission and capturing the decision of CTBT signatories “to take all necessary measures to ensure the rapid and effective establishment of the future Comprehensive Nuclear-Test-Ban Treaty Organization”, including through financial support and engagement in the Preparatory Commission’s work to establish the CTBT verification system. In this regard, Russia has entered into a Facility Agreement with the CTBTO, which regulates the hosting, operation and maintenance of IMS stations and the cooperation with the CTBTO on related matters.  

Recommendation: States Signatories to the CTBT should consider reiterating the binding nature of the decisions and commitments they have undertaken in CTBT/MSS/RES/1 to “take all necessary measures to ensure the rapid and effective establishment” of the CTBTO, and in other legal agreements with the Preparatory Commission.

It is notable that from a domestic perspective, Russia has only revoked Article 1 of its ratification legislation and retained legislative provisions contained there (and in other decrees) that assign Governmental roles and responsibilities in implementing the treaty – including financial support to the CTBTO, engagement in the Preparatory Commission, maintenance of IMS stations in Russia, and supporting on-site inspections.  

Confidence-building after withdrawal 

This legislation also establishes that Russia’s implementation of the CTBT is contingent on their ability to maintain the combat readiness, reliability, and safety of their nuclear arsenal. The US resolution of ratification considered, and then rejected, by the Senate in 1999 contained very similar conditions – or ‘safeguards’. Any future US ratification resolution would probably include them too. This common ground has become a grey area in which both states question the other’s commitment to prohibit nuclear weapon test explosions. The US has argued that Russia has conducted nuclear weapons-related experiments that do not adhere to the US understanding of compliance with the CTBT. Russia in turn has argued that the US is preparing to re-start nuclear tests.  

The withdrawal of Russia’s ratification has cast a shadow over the CTBT. In this shadow, ambiguities and uncertainties in the interpretation and observation of treaty restrictions can grow into mistrust – taking State Signatories further from ratification and closer to a return to nuclear testing. Nuclear-armed Signatories should seek to understand how they each interpret testing restrictions and demonstrate how their nuclear weapon stockpile stewardship activities abide by those restrictions. The US has invited international observers to its nuclear testing site to explore options for confidence-building measures, and has proposed to work with others to develop a reciprocal regime in this regard. This is a welcome step towards transparency and confidence-building, and should be supported.  

Recommendation: States Signatories to the CTBT should consider welcoming efforts to build confidence that States are not conducting nuclear explosive tests pending the Treaty’s entry into force, and invite State Signatories to consider any voluntary transparency and confidence-building measures they may wish to take.

The CTBT anticipates that ambiguities or uncertainties may cause concern about possible non-compliance with the Treaty. Article IV Part C of the Treaty establishes a Consultation and Clarification mechanism that State Parties may use to clarify and resolve such ambiguities or uncertainties. This mechanism appears to have received relatively little attention while the Preparatory Commission developed other components of the CTBT verification regime, despite it being an indicative area of work for the Preparatory Commission in CTBT/MSS/RES/1. It presents opportunities for transparency and confidence-building that would be integral to the health of CTBT once it enters into force, and a framework in which to explore such measures until that time.  

Recommendation: States Signatories to the CTBT should note the anticipated role of consultation and clarification in resolving concerns about possible non-compliance with the basic obligations of the Treaty, and should consider inviting Working Group B to establish a programme of work to explore procedures for conduct of consultation and clarification.

The CTBT and the global arms control and disarmament system have been further weakened this month and require support. The recommendations in this paper for reiterating commitment to international obligations and starting new activities on confidence building and transparency provide some opportunities to reverse the downward trend.

1 Annex 2 States are those that had nuclear power or research reactors at the time of the treaty negotiations.
2 It is not immediately clear from the wording of Article XIV whether Russia has now no longer “deposited its instrument of ratification” for the purposes of entry-into-force. As depository for the Treaty, the UN Secretary-General through the UN Office of Legal Affairs may provide clarification on this when receiving Russia’s notification of its withdrawal of ratification.