Sixteenth Report of the Secretary-General on the Implementation of Security Council Resolution 2231 (2015)

December 15, 2023

Weapon Program: 

  • Nuclear
  • Missile

Related Library Documents: 

I. Introduction

1. Progress with regard to the Iranian nuclear issue has fallen short of the expectations of the participants in the Joint Comprehensive Plan of Action and the international community. Despite repeated calls for all parties concerned to renew dialogue and engagement aimed at a return to the full and effective implementation of the Plan and Security Council resolution 2231 (2015), diplomatic efforts remain at a standstill. While the current challenges to restoring the Plan are complex, I remain of the view that the Plan still represents the best available option for ensuring the exclusively peaceful nature of the Iranian nuclear programme and urge all parties to focus on their shared objectives of non-proliferation and regional security.

2. Calls remain on the Islamic Republic of Iran to refrain from taking further steps away from the full implementation of the Plan and to undo the steps it has taken since July 2019, which it had pledged were reversible. The United States of America would also need to lift or waive its sanctions as outlined in the Plan and to extend the waivers with regard to the trade in oil with the Islamic Republic of Iran. These measures are essential for preserving the Plan’s primary objectives.

3. In its most recent report, the International Atomic Energy Agency reported that its “verification and monitoring has been seriously affected by the cessation of Iran’s implementation of its nuclear-related commitments under the JCPOA”. The Agency has not been able to verify the total stockpile of enriched uranium in the Islamic Republic of Iran since February 2021, but it estimated that, as of 28 October 2023, the total stockpile of enriched uranium was 4,486.8 kg (which exceeds the 202.8 kg limit), including 599.8 kg enriched to 20% U-235 and 130.3 kg enriched to 60% U-235. The Agency also noted that, “in the event of a full resumption of implementation by Iran of its nuclear-related commitments under the JCPOA”, the Agency would need “to establish a new baseline” with regard to centrifuge and heavy water production.

4. The present report provides an assessment of the implementation of resolution 2231 (2015) since the issuance of my fifteenth report (S/2023/473) on 29 June 2023. Consistent with previous reports, the focus of the present report is on the relevant provisions set forth in annex B to the resolution, namely restrictions applicable to nuclear-related transfers, ballistic missile-related activities and transfers, as well as the assets freeze.