On 14 July 2015, Iran signed a nuclear agreement with the US and five other states (China, France, Germany, Russia and the UK).  The agreement, known as the JCPoA (Joint Comprehensive Plan of Action), was endorsed unanimously by the UN Security Council in resolution 2231 on 20 July 2015 and thereby became an international agreement to which all UN member states had a duty to adhere.  

The JCPoA placed severe restrictions on Iran’s uranium enrichment capabilities and its stockpile of enriched uranium.  For example, for the next 15 years, Iran’s level of enrichment was capped at 3.67%, the level appropriate for power generation reactors – 90% enrichment is required for a nuclear weapon – and its stockpile of enriched uranium was limited to 300kgs. 

Sir Simon Gass was the head of the UK team that took part in negotiating the agreement. In a letter to The Times on 16 June 2025, he wrote:

“… it is worth remembering that in 2015 a group of six countries, including the UK, negotiated with Iran the Joint Comprehensive Plan of Action (JCPoA) — an agreement that, if it were in force today, would restrict Iran to a mere 300kg of uranium enriched to no more than 3.67 per cent, far from the quantity or purity needed for a nuclear weapon. The agreement included an inspection regime of unprecedented intrusiveness to ensure Iran was not cheating. In return, Iran was promised relief from international economic sanctions.”

Not in force today

The JCPoA is not in force today, thanks to President Trump, who on 8 May 2018 during his first term unilaterally terminated US adherence to it and reapplied the crushing US economic sanctions on Iran that were lifted when it came into force in January 2016.  This inevitably meant that Iran’s adherence to the agreement was also at an end and Iran was no longer subject to the enrichment limitations imposed by it.  Shortly afterwards, his Secretary of State Mike Pompeo issued an ultimatum to Iran making 12 demands that it must satisfy before sanctions are lifted, one of them being the cessation of uranium enrichment.

The President took this action despite the fact that Iran was in full compliance with the agreement and had been since it came into force in January 2016.  From then on, the IAEA (International Atomic Energy Authority) issued quarterly reports on Iran’s compliance.  Its tenth such report on 9 May 2018, like all its predecessors, confirmed Iran’s compliance, IAEA Director General Yukiya Amano stating:

“Iran is subject to the world’s most robust nuclear verification regime under the JCPoA …. As of today, the IAEA can confirm that the nuclear-related commitments are being implemented by Iran.”

Trump ends restrictions on Iranian enrichment

The President portrayed his decision to terminate the JCPoA as a measure to prevent Iran from acquiring a nuclear weapon.  But that makes no sense, since eliminating the enrichment constraints of the JCPoA freed Iran to reach the 90% level of enrichment required for a nuclear weapon, if it had a mind to do so.  Today, according to the IAEA, Iran has roughly 440 kg of uranium enriched up to 60% purity.  That was made possible by the President’s termination of the JCPoA.

Today, the President regularly tells outrageous lies about the JCPoA.  For instance, on 3 March 2026, he said it gave Iran “the right to have top-of-the-line nuclear weapons”.   That is simply untrue.  In reality, the JCPoA restricted Iran’s level of enrichment to 3.67%, which is far from the level required for a nuclear weapon.  The President removed that restriction when he terminated the JCPoA.

On 28 January 2020, speaking alongside Benyamin Netanyahu in the White House, President Trump confessed:

“As everyone knows, I have done a lot for Israel: moving the United States Embassy to Jerusalem; recognizing — (applause) –- recognizing the Golan Heights — (applause) — and, frankly, perhaps most importantly, getting out of the terrible Iran nuclear deal.  (applause)”

Nuclear deal possible in May 2025

After he returned to office in January 2025, President Trump said on many occasions that he wanted a deal with Iran.  Needless to say, he  repeatedly emphasised that Iran mustn’t develop nuclear weapons, but at the outset it wasn’t clear if the US would agree to limited uranium enrichment.

In May 2025, when negotiations were ongoing with the US, Iran stated publicly that, in exchange for the lifting of US sanctions, it was prepared to agree to a deal in which the enrichment level was limited to 3.67%.  This offer was made public in an NBC News report on 14 May 2025:

“Iran is ready to sign a nuclear deal with certain conditions with President Donald Trump in exchange for lifting economic sanctions, a top adviser to Iran’s supreme leader told NBC News on Wednesday. 

“Ali Shamkhani, a top political, military and nuclear adviser to Iranian Supreme Leader Ayatollah Ali Khamenei, is one of the most senior Iranian officials to speak publicly about the ongoing discussions. 

“He said Iran would commit to never making nuclear weapons, getting rid of its stockpiles of highly enriched uranium which can be weaponized, agree to enrich uranium only to the lower levels needed for civilian use, and allow international inspectors to supervise the process, in exchange for the immediate lifting of all economic sanctions on Iran.

“Asked if Iran would agree to sign an agreement today if those conditions were met, Shamkhani said, Yes.”

The US could have taken up that proposal and reinstated something like the JCPoA, but it didn’t.  Instead, it aborted its ongoing negotiations with Iran and joined Israel in aggression against Iran.

Memorandum of Understanding

The Memorandum of Understanding (MOU) signed by the US and Iran on 17 June 2026 states the following on the nuclear issue:

“The Islamic Republic of Iran reiterates that it will never produce nuclear weapons. The Islamic Republic of Iran and the United States have agreed that the fate of enriched material and the fate of all other mutually agreed nuclear-related issues, including Iran’s nuclear needs, will be adequately addressed in a final agreement; the final agreement will confirm the provisions of this Article.” 

Iran’s undertaking there that it will never produce nuclear weapons reaffirms a position it has maintained since it joined the NPT (Nuclear Non-Proliferation Treaty) in 1970 as a “non-nuclear-weapons” state.  Under Article II of the NPT, “non-nuclear-weapons” state members are required to undertake “not to manufacture or otherwise acquire nuclear weapons or other nuclear explosive devices”. 

(By contrast, Israel opted out of the NPT so that it was free to acquire nuclear weapons and other nuclear explosive devices – and it did so over 50 years ago in the late 1960s.)

In return for surrendering its right to develop nuclear weapons, the NPT grants “non-nuclear-weapon” states like Iran the right to develop a civil nuclear programme.   Article IV(1) of the treaty makes this clear: 

“Nothing in this Treaty shall be interpreted as affecting the inalienable right of all the Parties to the Treaty to develop research, production and use of nuclear energy for peaceful purposes.”

So, on the face of things, the NPT gives all “non-nuclear-weapon” states what it calls an “inalienable right” to uranium enrichment on their own soil, so long as the enrichment is not for weapons manufacture.  Argentina, Brazil, Germany, Japan and the Netherlands are all in the same position as Iran. They are all “non-nuclear-weapon” state parties to the NPT. All of them have uranium enrichment facilities. 

For more than a decade from 2003 onwards Iran resisted fierce pressure from the US and its allies to cease enrichment.  Its right to enrichment was conceded in the JCPoA.  It can be taken for granted that in upcoming negotiations with the US Iran will resist any proposal that cancels that right.  But it will probably be prepared to accept some restrictions on the enrichment level and to downblend the existing 60% enriched uranium under IAEA supervision.  It’s highly unlikely that the US will be prepared to go back to war to enforce a more restrictive regime.

David Morrison

1 July 2026