Former US President Donald Trump has dramatically shifted his stance on the UK’s Chagos Islands agreement, creating diplomatic uncertainty just days after Washington formally endorsed the sovereignty transfer plan. Through his Truth Social platform, Trump issued a stern warning to UK Prime Minister Sir Keir Starmer, characterizing the arrangement as a “big mistake” that would constitute “a blight on our Great Ally.”
The controversial agreement, announced in May 2026, would transfer sovereignty of the British Indian Ocean Territory to Mauritius while maintaining UK control over the strategically vital Diego Garcia military base through a 99-year leaseback arrangement. This joint UK-US facility serves as a critical staging post for military operations in the Indian Ocean region.
Trump’s intervention represents his third position change on the matter within months, having previously described the transfer as an “act of great stupidity” before briefly endorsing it as the “best” available option. His latest statement emphasized that “Leases are no good when it comes to Countries” and warned that Starmer was “losing control of this important Island.”
The surprising critique comes despite the US State Department’s official endorsement of the agreement earlier this week. White House press secretary Karoline Leavitt clarified that Trump’s social media post should be considered official administration policy, stating: “When you see it on Truth Social you know it’s directly from President Trump, that’s the beauty of this president in his transparency.”
UK officials maintained their support for the agreement, with the Foreign Office emphasizing that the arrangement remains “crucial to the security of the UK and our key allies, and to keeping the British people safe.” The legislation implementing the agreement has faced parliamentary delays, with no current timeline for its next consideration in the House of Lords.
The political opposition in Britain seized on Trump’s comments, with Shadow Foreign Secretary Dame Priti Patel demanding that Starmer “finally saw sense, U-turned and scrapped this appalling deal altogether.” Reform UK leader Nigel Farage characterized it as “the worst deal in British history.”
Meanwhile, Chagossian activists have intensified their opposition to the transfer. Four islanders recently occupied a remote atoll in protest, refusing evacuation orders from British maritime patrols. One protester, Misley Mandarin, declared they would have to “drag me from my beach,” arguing that Mauritius never legitimately owned the islands historically.
The archipelago has been under British control since 1814, purchased for £3 million in 1965. Mauritius maintains that it was illegally compelled to relinquish the territory during independence negotiations. The construction of the Diego Garcia base in the late 1960s involved the forced displacement of thousands of Chagossians, many of whom eventually settled in the UK, Mauritius, and Seychelles.