The UK will not be involved in Donald Trump’s blockade of the Strait of Hormuz, it is understood.
The US president threatened to stop tankers from entering or leaving the key oil and gas shipping lane – which has been throttled by Iran in retaliation for the US-Israel war against it, sending energy prices soaring.
After US-Iranian peace talks in Pakistan ended without a deal, Mr Trump lambasted Iran for failing to release its grip on the strait and commit to giving up its nuclear ambitions.
He wrote on his Truth Social platform that the US military would start “blockading any and all ships trying to enter, or leave, the Strait of Hormuz”.
He said the US navy would also “seek and interdict every vessel in International Waters that has paid a toll to Iran. No one who pays an illegal toll will have safe passage on the high seas”.
Mr Trump added, without elaborating: “Other Countries will be involved with this Blockade.”
But Britain will not play a part in the move, the Press Association understands.
A Government spokesperson said: “We continue to support freedom of navigation and the opening of the Strait of Hormuz, which is urgently needed to support the global economy and the cost of living back home.
“The Strait of Hormuz must not be subject to tolling.
“We are urgently working with France and other partners to put together a wide coalition to protect freedom of navigation.”
Sir Keir Starmer highlighted “the need to work with a wide coalition of partners to protect freedom of navigation” in the strait in a conversation with French President Emmanuel Macron.
A Downing Street spokesperson said: “The leaders discussed the situation in the Middle East and the importance of de‑escalation across the region. The Prime Minister stressed the need for a lasting ceasefire, with both leaders agreeing that any ceasefire must include Lebanon to support wider regional stability.
“They agreed on the strategic importance of the Strait of Hormuz for global trade and energy supplies, and on the need to work with a wide coalition of partners to protect freedom of navigation.”
The call on Sunday afternoon took place before Mr Trump threatened a blockade, it is understood.
US Central Command, which is responsible for American military operations in the Middle East, said US forces “will not impede freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports”.
In a statement that appeared to contradict Mr Trump’s threat to stop all ships, the military said only those “entering or departing Iranian ports and coastal areas” would be affected by the blockade.
Sir Keir has previously said “as many partners as possible” must be involved in coming up with a “viable plan” to reopen the maritime pinch point, pointing to the UK’s role in hosting talks on the issue with a coalition of countries.
The third such meeting convened by Britain is set to take place this week, following a virtual meeting of more than 40 nations chaired by the Foreign Secretary and a gathering of allied military officers.
Discussions included looking at issues such as clearing mines that have possibly been laid by Tehran to sink ships in the sea passage.
Mr Trump told Fox News “the UK and a couple of other countries are sending mine sweepers” to the strait, and “it won’t take long to clean it out”.
The Prime Minister previously said UK mine hunting systems were already in the region. But this is thought to refer to minesweeping drones which could be deployed once the situation stabilises, and distinct from Mr Trump’s blockade.
Sir Keir – who faced fresh personal criticism from the US president – earlier on Sunday urged the US and Iran “to find a way through” after their 21-hour negotiations in Islamabad collapsed, casting uncertainty over the shaky two-week truce.
In a readout of the Prime Minister’s call with the Sultan of Oman, His Majesty Sultan Haitham bin Tarik al Said, a Downing Street spokeswoman said: “They discussed the peace talks held in Pakistan over the weekend and urged both sides to find a way through.
“It was vital there was a continuation of the ceasefire, and that all parties avoided any further escalation, the leaders agreed.”
Mr Trump meanwhile continued to pour scorn on Nato and the UK over their refusal to support offensive operations against Iran, calling the defensive alliance “shameful”.
The Republican leader again compared Sir Keir to Neville Chamberlain, whose premiership was defined by his 1930s appeasement of Nazi Germany.
Mr Trump told Fox News: “He made a public statement that ‘we will send equipment after the war is over’, that’s a Neville Chamberlain statement.”
The president said talks in Pakistan involving US vice-president JD Vance “went well, most points were agreed to, but the only point that really mattered, nuclear, was not”.
