The UK agreed to cede an Indian Ocean archipelago to Mauritius while retaining control of a strategic military base on one of the islands, ending a long-running negotiation that had become a point of controversy for British premier Keir Starmer.
(Bloomberg) — The UK agreed to cede an Indian Ocean archipelago to Mauritius while retaining control of a strategic military base on one of the islands, ending a long-running negotiation that had become a point of controversy for British premier Keir Starmer.
Under the deal with Mauritius, the UK will pay an average of £101 million ($136 million) annually for continued use of the facility, Starmer told a news briefing on Thursday, in the first confirmation of the terms of the pact. The UK said the net present value of the payments is £3.4 billion, due to the way government accounting measures long-term investments.
Finalizing the deal achieves a key foreign policy aim for Starmer because it ends the uncertainty over the future of the base on Diego Garcia, a strategically valuable British-US facility that gives rapid access to East Africa, the Indo-Pacific, the South China Sea and the Persian Gulf. It was used during American campaigns in the Middle East and Afghanistan and also hosts a critical satellite communications system.
“The base is one of the most significant contributions that we make to our security relationship with the United States,” Starmer said at the briefing. “We had to act now because the base was under threat.”
British and US control over the base had been cast into doubt by the UK’s plan to cede the Chagos Islands to Mauritius, which followed a 2019 ruling by the International Court of Justice that Britain’s continued administration of the islands was unlawful. Mauritius, a nation of about 1.3 million people, in recent years has strengthened ties with China, fueling US worries about Beijing’s expanding military and economic influence in the region.
The Chagos Islands deal has been controversial for Starmer, given the large sums of money that Britain will pay to Mauritius to retain control of Diego Garcia. The UK’s main opposition Conservative Party and Nigel Farage’s Reform have regularly attacked Starmer over the deal, with Farage previously calling it a “surrender.”
The agreement announced Thursday ends six months of additional talks between the two countries, after the new Mauritian government led by Premier Navinchandra Ramgoolam expressed dissatisfaction over an initial accord announced on Oct. 4.
“It’s a great victory for us and the Mauritian nation,” Ramgoolam said. “It completes the process of decolonization that started in 1968.”
The announcement of the deal was held up on Thursday, however, by a last minute court challenge from a Chagos-born British national who claimed that the accord would violate the rights of the indigenous people of the Chagos Islands who had not been properly involved in the negotiations.
The legal challenge was the last chance for Chagossian people “to secure access to their homeland,” lawyers for the claimant, Bertrice Pompe, said in court filings.
“The severe obstacles which would be faced by British national Chagossians, who do not hold Mauritian nationality, in regards to participation in the future of their homeland needs to be addressed,” they said.
But the case was thrown out after the government argued it interfered with national security issues and foreign relations.
In 1965, Britain established the Chagos Islands as a separate territory, paid Mauritius £3 million in compensation and agreed to let the US operate a military base there in return for a discount on nuclear missiles and joint use of the facility.
Around 1,360 Chagossians were expelled from Diego Garcia, the largest island, to make way for the base, which began operations in 1973. Most ended up in the UK, Mauritius and the Seychelles, where they suffered discrimination and were given little help to rebuild their lives, according to Human Rights Watch.
The Chagos Islands have also been a point of interest in UK-US diplomacy given previous question marks over whether US President Donald Trump would back the agreement. That speculation was ended earlier this year when Trump said he was “inclined to go ahead” with the decision, speaking during a meeting with Starmer at the White House.
–With assistance from William Selway and Alister Bull.
(Updates with reaction and context starting in fourth paragraph.)
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