The UK government is re-examining its agreement to transfer sovereignty of the Chagos Islands to Mauritius. This decision comes after US President Donald Trump expressed his disapproval of the deal, calling it "terrible" at the UN General Assembly. The original agreement, made under former UK Prime Minister Sir Keir Starmer, would have the UK pay an average of £101m ($136m) per year to lease back a joint UK-US military base on the islands.
The deal was paused indefinitely in April after Trump withdrew his support. UK Defence Secretary Wes Streeting confirmed that the review is necessary because of the US's stance on the agreement. He emphasized that the UK needs to work with the US to find a solution that Trump can support. Streeting highlighted the importance of securing long-term certainty for the military base on Diego Garcia, the largest island in the Chagos archipelago.
The UK and Mauritius signed an agreement in May 2025, but the final draft of the bill to transfer sovereignty had not passed Parliament. The deal would have Britain hand over sovereignty to Mauritius while leasing back the Diego Garcia base for 99 years, at a total cost of £3.4bn. However, critics argued that the real cost could be around £35bn, adjusted for inflation, and that it risked allowing China to establish a presence on the archipelago.
Trump has been a vocal critic of the deal, previously calling it "a blight on our great ally" and an "act of total weakness". During a meeting with UK Prime Minister Andy Burnham at the UN General Assembly, Trump expressed his concerns, and Burnham agreed to review the situation. Burnham later stated that finding a resolution is critical to safeguarding the future of the military base, which is important for both the UK and the US.
The review of the deal has received mixed reactions from politicians. Conservative leader Kemi Badenoch called on Burnham to scrap the deal, while Reform UK leader Nigel Farage stated that "the Chagos deal is dead. Thank God." Streeting assured that no money will be handed over to Mauritius during the review period.
The Chagos Islands have been a point of contention since 1965, when Mauritius was forced to give up the islands to gain independence. Mauritius argues that it was illegally forced to cede the islands, and the ongoing legal process has raised concerns about the security of the military base. Every UK prime minister since Boris Johnson has considered the legal process a risk to the base's security.
The UK's review of the deal aims to find a solution that balances the interests of all parties involved. Streeting described the Diego Garcia base as "one of the most sensitive and valuable national security assets" and emphasized the need to find a deal that everyone can live with. The outcome of the review and its implications for the UK, US, and Mauritius remain to be seen.
Key points
- The UK is reviewing its deal to hand over the Chagos Islands to Mauritius due to a lack of US support.
