The United States has walked away from a coordinated diplomatic effort with the United Kingdom to address Iran's nuclear programme, according to senior officials in London and Washington. The decision, conveyed directly by President Donald Trump to Prime Minister Theresa May in a telephone call on Thursday, effectively ends weeks of joint British-American negotiations aimed at reviving the 2015 Joint Comprehensive Plan of Action (JCPOA).
The diplomatic push, led by UK Foreign Secretary Boris Johnson and US Secretary of State Rex Tillerson, had sought to broker a supplementary agreement with Iran that would address ballistic missile development and restrictions on uranium enrichment beyond 2025. European allies, including France and Germany, had expressed cautious support for the initiative.
President Trump's decision to withdraw from the talks came without prior consultation with British counterparts, according to a Downing Street source. The Prime Minister was informed of the President's change of position during a 20-minute call in which Mr Trump cited "fundamental flaws" in the existing agreement and expressed scepticism that any renegotiation could produce a deal acceptable to Washington.
The collapse of the Anglo-American initiative leaves the JCPOA in peril. Iran has consistently stated it will not renegotiate the terms of the original agreement, which lifted economic sanctions in exchange for restrictions on its nuclear programme. Tehran has also warned that it could resume enriching uranium to near weapons-grade levels if the deal collapses.
European signatories to the JCPOA, including the UK, France, and Germany, have reiterated their commitment to the agreement. However, without US participation, the economic incentives for Iran to remain within the deal are significantly diminished. European companies, wary of secondary US sanctions, may be reluctant to invest in Iran.
The breakdown in Anglo-American coordination on Iran marks a significant rift between two of the closest allies in the Western alliance. The UK had positioned itself as an intermediary between Washington and Tehran, leveraging its diplomatic ties with both sides. British officials expressed disappointment but stopped short of criticism.
A statement from the Foreign Office read: "The United Kingdom remains committed to the JCPOA and will continue to work with our international partners to ensure Iran does not develop a nuclear weapon. We regret that the United States has chosen not to pursue further diplomatic options at this time."
The move is consistent with President Trump's long-stated opposition to the JCPOA, which he has described as "the worst deal ever negotiated". During his presidential campaign, Mr Trump pledged to either renegotiate the agreement or withdraw from it entirely.
Analysts suggest the decision will embolden hardliners in Tehran who have argued that the United States cannot be trusted to honour international agreements. It also complicates European efforts to preserve the deal and may accelerate Iran's nuclear ambitions.
The UK has signalled that it will continue to engage with Iran bilaterally on issues of mutual concern, including regional stability and counterterrorism. However, without the weight of US economic and military power behind it, the British diplomatic initiative is significantly weakened.
The development comes as the United Nations nuclear watchdog, the International Atomic Energy Agency, is due to issue its next quarterly report on Iranian compliance with the JCPOA. Previous reports have confirmed Iran's adherence to the deal's terms.
