The head of the International Atomic Energy Agency (IAEA) is expected to visit Iran within days to inspect undeclared nuclear sites, a move that British officials describe as a pivotal moment in efforts to contain Tehran's nuclear programme. The inspection, agreed after weeks of intensive shuttle diplomacy coordinated by London, is seen as a critical step towards a broader deal aimed at averting a regional war.
Rafael Grossi, the IAEA director general, confirmed the visit late on Tuesday following a telephone conversation with Iran's nuclear chief, Mohammad Eslami. The exact locations and timing of the inspections remain classified, but diplomatic sources in Vienna indicate the focus is on two sites where traces of enriched uranium were detected in 2020. Iran has consistently denied any military dimension to its nuclear work, maintaining that its programme is peaceful.
Britain's role in orchestrating the breakthrough cannot be overstated. Foreign Secretary James Cleverly held multiple rounds of talks with his Iranian counterpart, Hossein Amir-Abdollahian, as well as with officials in Washington, Paris, Berlin and Brussels. The British approach, described by one insider as “quiet, persistent and deeply pragmatic”, helped overcome a stalemate that had persisted since the collapse of the 2015 nuclear deal, the Joint Comprehensive Plan of Action (JCPOA).
Under the JCPOA, Iran limited its enrichment activities in exchange for sanctions relief. The United States withdrew from the agreement in 2018 under President Donald Trump, prompting Iran to accelerate its nuclear advances. Negotiations to revive the deal have stalled since September 2022, with Western powers accusing Tehran of raising unreasonable demands.
Diplomatic sources in Geneva, where parallel talks on prisoner exchanges and financial transfers have been taking place, suggest that the inspection agreement is part of a larger framework. British envoys have been working on a roadmap that includes a phased lifting of sanctions, the unfreezing of Iranian assets abroad, and a mutual commitment to de-escalation. “The inspection is the key that unlocks the door,” a senior British diplomat said. “If Grossi can report that Iran is co-operating, we have a foundation for a sustainable deal.”
The urgency is heightened by the volatile regional situation. Israel has repeatedly threatened military action to prevent Iran from developing nuclear weapons. Iran's enrichment levels have reached 60 per cent, close to weapons-grade, with a stockpile that could yield enough fissile material for several bombs if further enriched. The United States has deployed additional naval assets to the Gulf, and the risk of a miscalculation is high.
British sources stressed that the goal is not to replicate the JCPOA but to craft a more durable agreement that addresses verification and longer centrifuges. “We are moving from crisis management to crisis resolution,” a Foreign Office official said. The United Nations Security Council is expected to be briefed on the inspection results next month.
Analysts caution against premature optimism. Iran's leadership remains divided between pragmatists and hardliners, who view compromise as a sign of weakness. The inspection must be unannounced and access must be unrestricted, as per IAEA protocols. Tehran has a history of last-minute demands that have derailed previous agreements.
Yet for now, the diplomatic track appears the only viable path. “The alternative,” one European envoy noted, “is a war no one wants.” The British-led initiative has garnered support from China and Russia, both of whom have veto power in the Security Council. Their backing is not unconditional, but it provides a rare moment of multilateral alignment.
The next steps depend on Grossi's report. If the inspections yield credible evidence of compliance, the parties may convene for formal negotiations before the end of the year. If not, the momentum could evaporate. Britain has committed to maintaining pressure on all sides, conscious that the window for diplomacy is narrowing. For the time being, the quiet work in Whitehall and Vienna has produced a result that many thought impossible: a chance to test Iran's intentions not with missiles, but with inspectors.
