Ministers originally intended for the deal to be ratified by the end of 2025, but the process has been repeatedly delayed amid opposition from Trump.
Foreign Office minister Hamish Falconer told MPs this week that “we are pausing for discussions with our American counterparts”.
He said: “There clearly has been a statement from the president of the US more recently which is very significant, and as I told the House we are now discussing those concerns with the US directly.”
“I can assure this House nothing in the treaty has changed since the US administration gave their original endorsement of the deal and we continue to work with Mauritius and the United States,” Falconer added.
However, a Foreign Office spokesman rejected Falconer’s characterisation of the situation as a “pause”, while a source added that he had “misspoken”.
“There is no pause,” the spokesman said. “We have never set a deadline. Timings will be announced in the usual way.
“We are continuing discussions with the US and we have been clear we will not proceed without their support.”
The Chagos bill has already been beset with delays after Tories in the Lords warned the agreement would violate a treaty between the UK and US dating from 1966.
That agreement had asserted Britain’s sovereignty over the islands and is meant to ensure they remain available to both sides for defence purposes.
In December, ministers said that the two countries were engaging in talks about updating this treaty in light of the new Chagos deal, but the talks have not been completed.
The UK was hopeful that the US was back onside after a spokesman for the state department said Washington supported the decision to hand over the islands to Mauritius.
But last week, Trump said: “Prime Minister Starmer should not lose control, for any reason, of Diego Garcia, by entering a tenuous, at best, 100-year lease.”
Asked during a press briefing whether Trump’s Truth Social message was the administration’s position, Karoline Leavitt, the White House press secretary, said: “The post should be taken as the policy of the Trump administration. It’s coming straight from the horse’s mouth.”
Since giving his approval to the deal, Trump has been relentlessly lobbied by prominent Republicans against it.
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