As President Donald Trump's administration finalises its deal with Iran, critics are quick to point out what is missing from the Memorandum of Understanding (MoU). The UK, which was a signatory to the previous Joint Comprehensive Plan of Action (JCPOA) in 2015, will be watching closely as the new agreement unfolds. Key differences between this MoU and its predecessor have sparked intense debate, particularly regarding Iran's nuclear programme, ballistic missile capabilities, and maritime access.
The JCPOA imposed strict limitations on Iran's enriched uranium stockpile, capping it at 300kg and restricting enrichment to 3.67% for 15 years – a level suitable for electricity generation but not nuclear warheads. However, following the US withdrawal from the agreement in 2018, Iran significantly escalated its nuclear activities, reportedly possessing around 440kg of 60% enriched uranium by February 2026. This material can be quickly further enriched to weapons-grade levels.
In contrast, the new MoU contains less specific detail on nuclear limitations. While Iran "reaffirms that it shall not procure or develop nuclear weapons" – similar language to the JCPOA – the document largely defers specifics to future negotiations. It states that both parties "agreed to discuss the issue of enrichment" and to "resolve the disposition of stockpiled enriched material pursuant to a mechanism that will be mutually agreed upon." This suggests that critical aspects of Iran's nuclear programme are still subject to forthcoming talks, rather than being definitively addressed in the current agreement.
Furthermore, the MoU's silence on Iran's ballistic missile capabilities has drawn attention. President Trump had previously stated the US was "destroying Iran's missile capabilities" at the outset of the conflict. However, the MoU text makes no mention of these missiles. This stands in stark contrast to President Trump's own criticism of the JCPOA in 2018, where he argued it failed to address Iran's ballistic missile development.
With the JCPOA serving as a comprehensive, two-year negotiated agreement and the MoU functioning as a framework for 60 days of talks towards a nuclear agreement, the two documents are fundamentally different. The UK will be scrutinising the new agreement's implications on maritime access, given Iran's strategic location in the Strait of Hormuz – a critical waterway for global oil trade.