Sir Keir Starmer has effectively shelved the UK’s agreement to hand sovereignty of the Chagos Islands to Mauritius, after the United States failed to provide the formal confirmation required for the treaty to be enacted — and with Parliament due to be prorogued in the coming weeks, time has run out.
UK government officials insist they are not abandoning the deal entirely, but a new Chagos bill is not expected to feature in the King’s Speech in mid-May. The sticking point is a formal exchange of letters from the US — a legal requirement for the treaty to proceed — which London has still not received.
The deal, signed in May 2025, would have seen the UK cede sovereignty of the British Indian Ocean Territory to Mauritius while paying an average of £101 million a year to lease back the joint UK-US military base on Diego Garcia, the largest island. It was initially welcomed by Washington, but early in 2026 President Trump reversed course, calling it an “act of total weakness” and posting on Truth Social urging Starmer not to “give away Diego Garcia” — describing it as “a blight on our great ally.” The contradiction was striking given that the US State Department had given the plan its official backing just a day before Trump’s post.
A government spokesperson maintained that Diego Garcia remained the central priority. “Ensuring its long-term operational security is and will continue to be our priority — it is the entire reason for the deal,” the spokesperson said, adding that the government would only proceed with US support.
Former Foreign Office permanent secretary Lord Simon McDonald told BBC Radio 4 that the government had been left with little choice. The UK had two objectives, he said — complying with international law and reinforcing the relationship with the United States — and with the US president openly hostile, putting the deal into the “deep freeze” was the only realistic option.
Conservative leader Kemi Badenoch welcomed the development, saying the deal should never have been on the table. Liberal Democrat foreign affairs spokesman Calum Miller criticised the handling of the whole affair as “totally shambolic” while also pointing the finger at Trump’s unreliability as an ally. Reform UK leader Nigel Farage called it “great news” and urged the government to help Chagossians resettle their homeland — a cause that has united critics of the deal across the political spectrum, with many Chagossians themselves opposing the agreement on the grounds that they want the UK to retain sovereignty so they can one day return.
