A Republican senator has introduced legislation that could torpedo Sir Keir Starmer’s controversial agreement to transfer the Chagos Islands to Mauritius.
Senator John Kennedy of Louisiana tabled the Diego Garcia Oversight Act today, which would grant US Congress the authority to block any handover of sovereignty.
The Prime Minister’s plan to cede the archipelago to Mauritius has attracted fierce criticism, with opponents highlighting the country’s close ties to both China and Iran.
Under the proposed arrangement, Britain would relinquish control of the islands while leasing back the strategically vital Diego Garcia military base, which serves as a joint US-UK facility amid the Middle East conflict.
The Trump administration has been among those voicing strong objections to the deal.
The proposed legislation would mandate Senate approval before any alterations could be made to the 1966 treaty that established American and British rights to operate from Diego Garcia.
Additionally, the bill would compel Downing Street to furnish Congress with a comprehensive report addressing the national security rationale behind any treaty modifications, the potential impact on US operational authority at the base, and any dangers arising from foreign sovereignty or military presence.
Senator Kennedy, a close presidential ally, framed the measure as essential for keeping the facility out of Beijing’s orbit.
US B-1 bombers on Diego Garcia | GETTY“When two countries shake hands on a treaty, one of them can’t start changing the terms without the other country agreeing to it,” he said, “that’s just common sense”.
“My bill would make sure that our friends in the UK don’t modify our treaty and hand this gift to China without giving the Senate a say”.
The Chagos deal was put on pause when the conflict in the Middle East began, with strong opposition placing a foot on Sir Keir Starmer’s neck.
Among the most passionate of critics was Reform UK leader Nigel Farage, who personally visited the islands to speak with recent settlers and see the implications of the deal first-hand.
Downing Street is considering giving the islands to Mauritius, however, No10 has insisted that they would keep control over the Diego Garcia airbase | GettyThe financial terms of Sir Keir’s agreement would see Britain pay Mauritius £35bilion across a 99-year lease period for continued access to Diego Garcia.
This latest dispute represents another friction point in deteriorating relations between London and Washington.
Tensions escalated when the Prime Minister declined to permit President Trump to launch initial military strikes against Iran from the Diego Garcia facility.
The base occupies a strategically crucial location that places Iran within range of American bombers, enabling continuous long-range missions including last year’s B-2 Spirit attack on Tehran.
Citing international law, Britain initially refused US requests to conduct operations from Diego Garcia and RAF Fairford.
Sir Keir subsequently reversed course, agreeing to grant American forces access to the base for “specific and limited defensive purposes”.
Speaking to The Telegraph, President Trump described the Prime Minister’s initial refusal to permit base access as unprecedented in the history of UK-US relations.
The president subsequently attacked Sir Keir over his perceived lack of backing for the Iran conflict, declaring he was “not Winston Churchill” and risked “ruining the special relationship”.
Mr Trump’s stance on the Chagos agreement has since shifted following sustained pressure from British and American intelligence services, alongside Republican lawmakers.
Senator Kennedy was instrumental in efforts earlier this year to derail the deal, co-signing a February letter with Senator Ted Cruz.
That correspondence urged Secretary of State Marco Rubio and Defence Secretary Pete Hegseth to reject the agreement outright and withdraw any diplomatic communications that had endorsed it.
