The UK has defended its proposed deal to transfer sovereignty of the Chagos Islands to Mauritius after Donald Trump criticised the move as an “act of great stupidity.”
Under the unratified agreement, Britain would hand over the islands while retaining the Diego Garcia military base under a 99-year lease to protect UK–US strategic interests.
While Trump warned the deal undermines US security, the UK says it safeguards the base amid legal challenges, and the agreement has previously received backing from the US administration.
The UK government has defended its proposed agreement to hand over sovereignty of the Chagos Islands to Mauritius after US president Donald Trump sharply criticised the deal, calling it an “act of GREAT STUPIDITY.”
Under the agreement, which is yet to be ratified, Britain would transfer sovereignty of the Indian Ocean archipelago to Mauritius while retaining the strategically important Diego Garcia military base under a 99-year lease, with an option to extend it by a further 40 years. The base hosts a joint UK–US military facility seen as critical to security operations in the Indo-Pacific.
Responding to Trump’s remarks, the UK government said the deal was designed to safeguard the future of the military base, arguing that Britain’s position had been weakened by recent court rulings that threatened its long-term control over the territory. Officials said the agreement ensures continued access for UK and US forces while resolving longstanding legal and diplomatic challenges.
Trump, however, claimed the handover would undermine US strategic interests. In a post on his Truth Social platform, he wrote: “Shockingly, our ‘brilliant’ NATO Ally, the United Kingdom, is currently planning to give away the Island of Diego Garcia, the site of a vital U.S. Military Base, to Mauritius, and to do so FOR NO REASON WHATSOEVER.”
He also suggested that the decision formed part of a broader pattern of strategic missteps, linking it to his argument for increased US control over territories such as Greenland.
Despite Trump’s criticism, the proposed deal has previously received support from Washington. In May, US Secretary of State Marco Rubio described the agreement as a “monumental achievement,” signalling bipartisan backing within the US administration at the time.
Prime Minister Sir Keir Starmer has said the lease arrangement for the Diego Garcia base would cost the UK £101 million annually. The government maintains that the agreement strikes a balance between upholding international law, addressing historical disputes, and protecting vital defence interests.
The Chagos Islands were separated from Mauritius in 1965, before Mauritian independence, and have long been the subject of international legal challenges and calls for decolonisation.
