House of Commons Library

The JCPOA and rising US-Iran tensions

Published Thursday, July 25, 2019

This Commons Library briefing paper looks at the Iran nuclear agreement (the JCPOA) and recent developments between the US and Iran, following the attack on tankers in the Gulf in June 2019.

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In 2015 Iran and the EU announced they had reached an agreement on the Iran nuclear issue. Under the Joint Comprehensive Plan of Action (JCPOA) Iran agreed to limit its nuclear programme and allow enhanced inspections by the International Atomic Energy Agency. In return, UN Security Council sanctions and multilateral and national sanctions were lifted. The UN Security Council endorsed the JCPOA in Resolution 2231.[1]

In May 2018, however, the US announced it was withdrawing from the deal and started to re-introduce sanctions. In April 2019 the Trump administration announced its intention to reduce Iran’s oil exports to zero. The US accuses Iran of using oil revenues to “support its destabilizing activities and fund terrorist proxies”, to finance its nuclear weapons and ballistic missile programmes and undermine the stability of the region, including threatening freedom of navigation through the Gulf. In November 2018 the US re-instated sanctions targeting both Iran and states that trade with it.

The JCPOA’s other signatories so far remain committed to the Agreement. The UK, France and Germany responded to the US withdrawal in 2015 by emphasising their continuing commitment to the JCPOA. The EU has passed legislation aiming to protect EU-Iran trade from the extraterritorial effects of US sanctions.

In April 2019 Iran warned it would start enriching uranium beyond the amount agreed in the deal if European countries did not do more to protect Iranian trade from the effects of US sanctions. In May Iran said it would no longer abide by the JCPOA limit of 300kg stored uranium enriched to 3.67% and later announced it would breach the stockpile limit by 27 June.

On 2 July the International Atomic Energy Agency confirmed that Iran had breached the 300kg limit for its stockpile of low-enriched uranium. On 7 July Iran said that it had begun enriching uranium over the limit of 3.67%, the concentration limit set out in the JCPOA.

These announcements came against a backdrop of rising tensions with the US. In the year since the US pulled out of the JCPOA and started re-imposing sanctions, Iranian oil exports have fallen from around 2.5 million barrels per day to below 1 million in April 2019. The Iranian rial has lost more than 60% of its value against the US dollar. The IMF predicts that inflation will hit 40% this year.

Tensions have significantly increased after two separate attacks on tankers in the Gulf region in May and June 2019. The UK Government agrees with Washington that Iran is responsible for the attacks. The then Foreign Secretary said “responsibility for the attacks almost certainly lies with Iran”, while the Minister for the Middle East said it is “almost certainly” the responsibility of the Islamic Revolutionary Guard Corps, arguing “no other state or non-state actor could plausibly have been responsible”.[2]

The US is sending an additional 1,000 troops to the Middle East, having already announced the deployment of an aircraft carrier group to the Gulf.

Many commentators have argued that the growing tensions could result in conflict by misunderstanding. The UK Government said in May it is concerned about “the risk of unintended escalation between the United States and Iran”. In June the Minister for the Middle East said the Government’s aim is to “de-escalate the situation”.


[1]    For more information see the UN Security Council backgrounder on Resolution 2231.

[2]    HC Deb 17 June 2019 c61


Commons Briefing papers CBP-8597

Authors: Louisa Brooke-Holland; Ben Smith

Topics: Arms control, Iran, Middle East, North America

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