LONDON — The British government has called for restraint in nuclear negotiations between the United States and Iran, warning that a rushed agreement could destabilise the Middle East. The appeal came as US Vice President Vance acknowledged that a “significant gap” persists between the two sides, despite reports of progress towards a new accord.
Speaking to journalists in Downing Street, a Foreign Office spokesperson said that while London supports diplomatic engagement, “any deal must be verifiable, robust, and contribute to long-term regional security.” The statement reflects growing anxiety among European allies that Washington may prioritise a headline-grabbing breakthrough over the technical rigour required to prevent Iranian nuclear breakout.
Negotiations in Vienna have entered a critical phase, with US and Iranian officials meeting indirectly through European mediators. Leaked details suggest the framework under discussion would limit Iranian enrichment levels in exchange for sanctions relief. However, Vance, in a press conference on Wednesday, cautioned that “the distance between what we can accept and what Tehran is demanding remains considerable.” He declined to specify the sticking points.
Analysts point to two principal obstacles: the scope of sanctions relief and the duration of restrictions on Iranian nuclear activity. Iran has insisted on a full and immediate lifting of all sanctions imposed since 2018, when the US withdrew from the Joint Comprehensive Plan of Action. Washington, meanwhile, wants phased relief tied to compliance milestones. The question of International Atomic Energy Agency access to military sites also remains unresolved.
Britain, along with France and Germany, has stressed the need for a deal that strengthens — rather than replaces — the JCPOA’s monitoring provisions. The original agreement, signed in 2015, was hailed as a landmark in non-proliferation but collapsed after President Trump’s withdrawal in 2018. Since then, Iran has accelerated its enrichment programme, stockpiling uranium close to weapons-grade.
Strategic analysts in London argue that the current negotiating window may be the best opportunity to restore constraints. “If this round fails, Iran could quickly cross the threshold to a nuclear weapon,” said Dr. Margaret Cole, a former director of the Royal Institute of International Affairs. “Yet a weak deal risks legitimising Iran’s nuclear progress without adequate oversight.”
Vance’s admission of a remaining gap has tempered expectations of a swift announcement. US officials have privately indicated that a deal is unlikely before the summer, given the complexity of technical annexes and the need for congressional consultation. Iran’s foreign ministry has echoed this caution, stating that “nothing is agreed until everything is agreed.”
The British position reflects a broader European calculation: to avoid a repeat of 2018, when Washington’s unilateral withdrawal left European allies scrambling to salvage the agreement. This time, London, Paris, and Berlin have insisted on a multilateral framework that includes guarantees against future US withdrawal — a demand Washington has resisted.
As negotiations continue, the risk of escalation remains. Israel has threatened pre-emptive strikes against Iranian nuclear facilities if a deal does not address its concerns. Britain, which maintains close intelligence ties with Israel, has urged “maximum restraint” on all sides. The Foreign Office spokesperson reiterated that “military action would be catastrophic and should be avoided at all costs.”
For now, the diplomatic track remains the preferred option. But Vance’s cautious language and Britain’s call for restraint underscore the fragility of the process. The world waits, as it has for decades, to see whether diplomacy or brinkmanship will prevail.
