The Iranian nuclear programme

Flags of the European Union, Iran, France, Germany and the UK

Flags of the European Union, Iran, France, Germany and the UK, © Florian Gaertner/photothek.net

14.03.2024 - Article

After a protracted conflict surrounding the dangerous Iranian nuclear programme, Germany, France, the UK, the US, Russia, China and Iran signed the Joint Comprehensive Plan of Action (JCPOA) on 14 July 2015 in an attempt to resolve this crisis at the negotiating table.

The chief negotiators of the E3/EU+3 group and Iran before the last plenary session in Vienna
The chief negotiators of the E3/EU+3 group and Iran before the last plenary session in Vienna© Photothek

The United Nations Security Council approved the JCPOA with Resolution 2231 (2015), and it took effect on 18 October 2015. As coordinator, the High Representative of the European Union plays a key role in the implementation of the JCPOA, which initially met with success. Until mid-2019, the International Atomic Energy Agency (IAEA) repeatedly confirmed in its quarterly reports that Iran was adhering to the JCPOA undertakings. Iran also benefited from the agreement. Sanctions were eased as agreed and the country’s economy grew.

The JCPOA in crisis

On 8 May 2018, US President Donald Trump announced the United States’ withdrawal from the JCPOA. The US re-imposed the sanctions against Iran that it had suspended and gradually enforced further restrictive measures. Many of these measures are secondary sanctions, which also affect Iran’s trading partners in third countries.

Iran has been gradually abandoning its nuclear-related commitments under the JCPOA since 1 July 2019 and further stepped up its systematic violations of the JCPOA on the basis of a “strategic nuclear law” passed in December 2020. Iran increased its production of low-enriched uranium, raised the enrichment level to up to 60 percent, abandoned the agreed limits for research and development on advanced centrifuges, recommenced uranium enrichment at the underground plant in Fordow, reduced transparency with regard to its nuclear programme and started experiments to extract uranium metals without plausible civilian justification.

The Vienna talks on the restoration of the JCPOA

The US administration under President Biden announced its determination to return to the nuclear agreement and to repeal the nuclear-related secondary sanctions imposed or reinstated by the previous administration, provided Iran also adhered once again to its obligations. Negotiations between the JCPOA participants and the US were held in Vienna from April to June 2021 and from November 2021 to March 2022, during which an agreement on these issues was outlined. However, Iran rejected the compromise packages submitted in March and August 2022 by the EEAS as coordinator, and so prevented the revival of the JCPOA. In view of Iran’s significant and ongoing breaches of the JCPOA, the E3 has retained the nuclear-related sanctions at EU level and under UK law, although under the JCPOA these were due to be repealed on Transition Day (18 October 2023). This step does not mean the end of the JCPOA, but can be reversed if Iran lives up to its obligations under the agreement.

Since the failure to restore the JCPOA in 2022, no further negotiations of this kind have taken place. The Iranian nuclear programme has now reached a particularly dangerous level. The German Government continues to seek a diplomatic solution to this crisis.

What are the key elements of the JCPOA?

The signatures of the negotiating partners
The signatures of the negotiating partners© Photothek/Imo

Between July 2015 and January 2016, Iran had six months after the conclusion of the agreement to significantly scale back its nuclear programme. Since that time, the programme has been subject to strict constraints. In particular, Iran undertakes to:

  • dismantle two‑thirds of its centrifuges
  • export almost all of its stockpile of enriched uranium to Russia
  • render the core of the plutonium reactor in Arak unusable
  • use only 5060 first‑generation centrifuges in the Natanz plant to enrich uranium for the next ten years
  • restrict its uranium enrichment to 3.67 percent for a period of 15 years
  • stockpile no more than 300 kilograms of low‑enriched uranium (uranium hexafluoride) in the country at any time
  • stop using the underground plant in Fordow to enrich uranium
  • convert the research reactor in Arak so that it cannot be used to make weapons‑grade plutonium
  • refrain from activities connected with spent fuel reprocessing for a period of 15 years
  • submit to the strictest IAEA controls in the world and provisionally apply the IAEO’s Additional Protocol
  • conduct future trade in nuclear technology and dual‑use goods via an internationally monitored Procurement Channel under the control of the United Nations Security Council.

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