UK retains US base access as Chagos sovereignty transfers to Mauritius
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Britain is ceding Chagos sovereignty to Mauritius while locking in US military access to Diego Garcia under a $100 million-a-year deal.
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A US B-1B Lancer landing after a Bomber Task Force mission at Naval Station Diego Garcia last year (US Air Force/AP)
The United Kingdom has signed a landmark agreement transferring sovereignty of the Chagos Islands to Mauritius, while simultaneously locking in a long-term lease of the Diego Garcia military base for use by both the UK and the United States, effectively ending a decades-long immediate decolonization and moving instead to maintaining strategic military control.
The Indian Ocean archipelago, previously under British colonial rule since 1814, will now officially fall under Mauritian sovereignty. Under the terms of the deal, the UK will lease back Diego Garcia for at least 99 years, allowing the continuation of joint UK-US operations at the site for over $100 million annually.
US Secretary of State Marco Rubio hailed the agreement as a “monumental achievement" and noted that US President Trump had personally endorsed the deal during a White House meeting with British Prime Minister Keir Starmer in February.
Diego Garcia leased for 99 years to preserve US military base
Speaking from the UK military headquarters in Northwood, Prime Minister Starmer emphasized the base’s critical role in intelligence operations and regional security, saying the agreement represents “one of the most significant contributions that we make to our security relationship with the United States.”
Starmer added that while many aspects of the base’s operations are classified, it has been instrumental in what he claimed were "counter-terrorism operations" in Iraq and Afghanistan and serves to protect the lives of both British and American forces.
The U.S. welcomes the historic agreement between the UK and Mauritius on the future of the Chagos Archipelago. This agreement secures the long-term, stable, and effective operation of the joint U.S.-UK military facility at Diego Garcia, which is critical to regional and global…
— Secretary Marco Rubio (@SecRubio) May 22, 2025
The Chagos Archipelago has been home to the Diego Garcia facility since the late 1960s, when the UK expelled thousands of Chagossian residents to make way for US construction. Although the UK paid Mauritius three million pounds at the time, Mauritius has long claimed the islands were taken under duress during independence negotiations.
Mauritius claims victory, but Chagossians remain divided
Mauritian Prime Minister Navin Ramgoolam called the agreement a “great victory for the Mauritian nation” and declared that “we are completing the process of total decolonization,” marking the culmination of years of legal and diplomatic pressure that included rulings from the International Court of Justice and the United Nations.
In 2019, the ICJ concluded that Mauritius had been unlawfully denied full sovereignty and called on Britain to end its rule “as rapidly as possible.” The UN followed in 2021, with a maritime court ruling rejecting UK sovereignty over the islands.
Still, the agreement has divided the Chagossian community. While some support the formal recognition of Mauritian sovereignty, others oppose the deal on the grounds that it does not guarantee their right of return to the islands, decades after their forced displacement.
This rushed deal was based on narratives created by (UK) lawyers working for (now disgraced) Mauritian politicians and without reference to real world concerns or the human rights of the Chagossians. @DavidLammy @SDoughtyMP @PeterKLamb @AndrewRosindell https://t.co/q0gkxKoLyJ
— Chagossian Voices (@ChagossianVoic2) November 27, 2024
Peter Lamb, MP for Crawley, home to the largest Chagossian diaspora in Britain, condemned the move. Speaking in Parliament, he asked, “What should I tell my Chagossian constituents, when they ask the moral basis upon which the UK is ignoring their right to self-determination while we fight for it in Ukraine for Ukrainians?”
British Parliament split as critics call it a ‘giveaway to China’
While the Labour government has praised the agreement as a "diplomatic success", opposition voices have criticized it as a strategic blunder. Conservative Party leader Kemi Badenoch warned that the Chagos Islands had been British since 1814 and said, “Only Keir Starmer’s Labour Party would negotiate a deal where we’re paying to give something away,” adding that Mauritius is an ally of China.
Right-wing populist leader Nigel Farage echoed the concerns, calling the deal a “gift to Beijing” and claiming it weakens British influence in a region already under increasing strategic contest.
The UK government, however, says the arrangement has full backing from its Five Eyes intelligence partners, including the US, Canada, Australia, and New Zealand, and maintains that continued joint military access to Diego Garcia secures long-term security for all allies.
