British Prime Minister Keir Starmer is blocking a request by US President Donald Trump to allow American aircraft to use UK military bases for potential strikes on Iran, saying such action would breach international law, according to a report by British daily The Times.
Under long-standing agreements between London and Washington, British bases may only be used for military operations against third countries with prior approval from the UK government.
The move prompted Trump on Wednesday to withdraw his support for Starmer’s agreement to transfer sovereignty over the Chagos Islands to Mauritius.
In a post on his Truth Social platform, Trump referred to Iran and the potential role Britain might play in any attack, suggesting UK participation would be legal under international law because Iran could pose a threat to the United Kingdom.
Trump, who is considering military action against Iran, warned Britain not to “give away” the strategic Indian Ocean base of Diego Garcia, saying it would be vital if the United States launches strikes.
The comments came hours after the US State Department reiterated support for Starmer’s deal to return the Chagos Islands to Mauritius, under which Britain would lease the joint US-UK base at Diego Garcia for 100 years.
“Prime Minister Starmer should not lose control, for any reason, of Diego Garcia, by entering a tenuous, at best, 100 Year Lease,” Trump wrote.
“This land should not be taken away from the U.K. and, if it is allowed to be, it will be a blight on our Great Ally,” he added.
“We will always be ready, willing, and able to fight for the U.K., but they have to remain strong in the face of Wokeism, and other problems put before them. DO NOT GIVE AWAY DIEGO GARCIA!”
Britain retained control of the Chagos Islands after Mauritius gained independence from British rule in the 1960s, forcibly evicting thousands of residents who later pursued legal challenges seeking compensation.
Trump dismissed the claims of Chagossians as “fictitious in nature.”
Responding to Trump’s remarks, a British Foreign Office spokesperson said the agreement secures the long-term future of the joint UK-US base.
“The agreement we have reached is the only way to guarantee the long-term future of this vital military base,” the spokesperson said, describing the facility as “crucial to the security of the UK and our key allies.”
Trump’s latest shift comes as he weighs possible strikes on Iran, where authorities last month killed thousands of people during a crackdown on mass demonstrations.
US envoys on Tuesday held new indirect negotiations in Geneva with Iran’s top diplomat, pressing Tehran for major concessions starting with its nuclear program.
The United States joined Israel in bombing Iran in June, striking nuclear facilities while Israel carried out a broader campaign.
“Should Iran decide not to make a Deal, it may be necessary for the United States to use Diego Garcia, and the Airfield located in Fairford, in order to eradicate a potential attack by a highly unstable and dangerous Regime,” Trump said, referring to a US air base in England.
He said he was concerned about “an attack that would potentially be made on the United Kingdom, as well as other friendly Countries.”
Just Tuesday, the US State Department announced three days of talks next week with Mauritius on maintaining the Diego Garcia base and said Washington supports the UK-Mauritius agreement.
“The United States supports the decision of the United Kingdom to proceed with its agreement with Mauritius concerning the Chagos archipelago,” the department said.
Asked which statement reflected US policy, White House Press Secretary Karoline Leavitt said Trump’s social media post came directly from the president and “should be taken as the policy of the Trump administration.”
When Starmer’s Labour government first reached the deal last year, US Secretary of State Marco Rubio described it as “historic.”
Trump initially condemned the agreement as an “act of GREAT STUPIDITY,” later said he accepted it after speaking with Starmer, and now appears to have reversed his position again.