US Support Critical for UK-Mauritius Deal on Chagos Islands, Military Base

The fate of the Chagos Islands, a strategically vital Indian Ocean archipelago home to a joint U.K.-U.S. military base, is currently uncertain due to the U.S. position on a sovereignty transfer agreement between Britain and Mauritius.

U.K. Defense Secretary Wes Streeting stated that officials are reviewing the pact after former President Donald Trump reiterated his criticism of the U.K.-Mauritius deal, calling it a "terrible deal" during a recent meeting with Prime Minister Andy Burnham. Streeting indicated that the agreement "can't go ahead without American support."

The U.S. military base on Diego Garcia, the largest island in the Chagos chain, has been described by the U.S. as "an all but indispensable platform" for security operations across the Middle East, South Asia, and East Africa. The base supports approximately 2,500 personnel and has been instrumental in U.S. military operations for decades. It has also been acknowledged as a site used for clandestine rendition flights of terror suspects.

Historical Context of the Dispute

The Chagos Islands have been under British control since 1814. In 1965, the U.K. separated the islands from Mauritius, a former British colony, three years before Mauritius gained independence. The U.K. then designated the archipelago as the British Indian Ocean Territory.

During the 1960s and 1970s, the U.K. forcibly evicted an estimated 2,000 inhabitants from the islands to make way for the construction of the Diego Garcia base. In recent years, Britain's control over the archipelago and the displacement of its population have drawn increasing international criticism. The United Nations and the International Court of Justice have urged the U.K. to end its "colonial administration" and transfer sovereignty to Mauritius.

Recent Dealings and Trump's Influence

Negotiations between the U.K. and Mauritius regarding the islands began in 2022. An agreement was reached in May 2025, after the U.K. government secured the backing of the Trump administration. Under this pact, the U.K. would pay Mauritius at least 120 million pounds (approximately $159 million) annually to lease back Diego Garcia for a minimum of 99 years.

Initially, the U.S. government welcomed the agreement. However, in January, former President Trump voiced strong opposition on social media, deeming the transfer "an act of GREAT STUPIDITY." This opposition effectively halted the deal, and related legislation failed to pass before the U.K. Parliament's session concluded in May.

The situation remained on hold until Trump's recent remarks to Prime Minister Burnham. Following Trump's renewed criticism, Burnham expressed confidence in the U.K.'s ability to reach an agreement with the U.S. Streeting acknowledged that Trump's position has not changed, emphasizing the need for a solution that accommodates the interests of Britain, the U.S., and Mauritius.

Meanwhile, Conservative Party defense spokesperson James Cartlidge urged Burnham to abandon the deal entirely and reallocate the funds to support U.K. troops.