Britain’s deal to hand the Chagos Islands back to Mauritius is under review again, after Donald Trump told the UN General Assembly this week that the agreement was “terrible.” UK Defence Secretary Wes Streeting confirmed the reversal to the BBC, saying the government has “to” revisit the deal because “the United States doesn’t support it.”
For London and Washington, the fight is largely about Diego Garcia — the archipelago’s largest island and home to a joint UK-US military base considered one of the most strategically valuable in the Indian Ocean. For Mauritius, and for the African states that have backed its claim for years, the dispute has never really been about the base. It has been about whether a colonial-era land grab still stands sixty years later.
Britain separated the Chagos Archipelago from Mauritius in 1965, three years before Mauritian independence, forcibly displacing the islands’ Chagossian population in the process. Mauritius has argued ever since that its independence was made conditional on giving up the territory — a bargain it never freely agreed to. The legal campaign built momentum slowly, through UK court challenges brought by Chagossian activists in the late 1990s and a successful 2015 tribunal ruling against Britain’s marine protected area around the islands, before reaching the International Court of Justice.
That case produced the moment African governments still point to. In February 2019, the ICJ issued an advisory opinion finding that Mauritius’s decolonisation had never been lawfully completed and that Britain’s continued administration of the islands was unlawful. Three months later, the UN General Assembly took the unusual step of putting that opinion to a vote — a resolution brought specifically by African states, demanding Britain withdraw its “colonial administration” within six months. It passed 116 votes to six, with only Britain, the US and four allies opposed. Mauritius’s prime minister at the time, Pravind Jugnauth, told the assembly the vote was a signal that “colonialism can no longer be tolerated.” Britain ignored the deadline.
It took until 2024 for a Labour government under Keir Starmer to agree, in principle, to hand sovereignty back while leasing the Diego Garcia base for 99 years at a cost UK officials put at £3.4bn, though critics say the real figure could reach £35bn once inflation is factored in. That deal has now been paused twice by two different UK governments, both times because Trump withdrew his backing. Mauritius’s position throughout has been that none of this changes anything legally.
When Trump first criticised the agreement in January, Mauritius’s attorney general, Gavin Glover, responded flatly: “The sovereignty of the Republic of Mauritius over the Chagos archipelago is already recognised without ambiguity under international law and should no longer be a subject for debate.”
Whether that confidence survives a second round of US objections is now Prime Minister Andy Burnham’s problem to manage, not Mauritius’s. Streeting said no money will change hands “at this stage” while officials try to find a version of the deal Trump can accept. For Mauritius, the wait continues — a position it has now held, in one form or another, for sixty years.
