Donald Trump said he was “very disappointed” in Sir Keir Starmer for initially refusing to allow the use of the UK-US Diego Garcia base to target Iran.
The US president said it “took far too long” for the Prime Minister to change his mind.
Sir Keir announced late on Sunday that US forces would be allowed to operate from British bases against Iran, but only in a limited role targeting missile sites.
Mr Trump highlighted the issues around Diego Garcia, in the Chagos Islands which are at the centre of a diplomatic row between the UK, US and Mauritius, in a Telegraph interview.
The US president criticised the refusal to grant permission to use the base for the initial strikes against Iran’s military and leadership.
“That’s probably never happened between our countries before,” he said, adding: “It sounds like he was worried about the legality.”
Referring to Sir Keir’s change of position, he added: “It is useful. It took far too much time. Far too much time.”
Sir Keir’s announcement came just hours before a drone hit the RAF Akrotiri base in Cyprus.
Officials said RAF Akrotiri was continuing to operate as normal despite the attack but family members of personnel had been moved away from the base as a precaution.
The drone is believed to have been launched before Sir Keir announced he had allowed US forces to use British bases rather than in retaliation to the policy shift.
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