The UK government is finalising an agreement with Mauritius over the future of the Chagos Islands, Downing Street has confirmed.

Under the proposed deal, Mauritius would gain sovereignty over the Chagos Archipelago—currently known as the British Indian Ocean Territory—while allowing the US and UK to continue operating a military base on Diego Garcia for an initial 99-year period. This arrangement would be funded by the UK government.

Sources suggest the UK is not waiting for final approval from US President Donald Trump, despite earlier statements by Foreign Secretary David Lammy that US objections could block the deal.

Mauritius confirmed that both governments are working toward finalising the agreement. The plan was initially announced last October during negotiations with former Mauritian Prime Minister Pravind Jugnauth. However, his successor, Navin Ramgoolam, raised concerns, causing delays. Talks were further slowed after Trump’s election as negotiators awaited feedback from the new US administration.

While critics like UK Conservative leader Kemi Badenoch argue the deal is not in Britain’s national interest, US officials have also voiced concerns. Last October, Secretary of State Marco Rubio warned the deal could threaten US security due to Mauritius' ties with China. Reform UK leader Nigel Farage claimed the deal would face "outright hostility" from Trump’s team.

Yet Trump appeared more supportive last month. During a press conference with UK Prime Minister Sir Keir Starmer, he said discussions were underway and suggested a long-term lease—possibly up to 140 years—could work well for both nations.

The current plan would give the UK a 99-year lease on Diego Garcia, with a possible 40-year extension. While reports have estimated the deal's cost to the UK at £18 billion, the Foreign Office has dismissed those figures as inaccurate. The government has yet to disclose the full cost but pledged transparency with Parliament once the deal is finalised.

The Chagos Islands were separated from Mauritius in 1965 when the country was still under British rule. Britain paid £3 million for the territory, but Mauritius claims it was coerced into giving up the islands as a condition for independence.

In the late 1960s, the UK allowed the US to build a base on Diego Garcia, forcibly removing thousands of Chagossians. International pressure has since mounted for the UK to return the islands, with both the UN’s International Court of Justice and General Assembly siding with Mauritius.

The previous Conservative government began negotiations in 2022 but left office before a deal was concluded. Photo by Anne Sheppard, Wikimedia commons.