The Government announced a “historic” deal on Thursday to renounce UK sovereignty over a chain of Indian Ocean islands claimed by Mauritius - but it will retain effective control over one island that houses a vital US military base.
Under the deal reached by Sir Keir Starmer with Mauritius Prime Minister Pravind Jugnauth, the British Indian Ocean Territory (BIOT) or Chagos Islands is to be handed back more than five decades after the rest of Mauritius won independence from the UK.
But according to the Foreign Office, the UK will remain “authorised to exercise the sovereign rights of Mauritius on Diego Garcia”, where the US-UK base occupies a strategically vital role amid growing tensions with China and India.
The United States is on board with the deal, it said, after years of dispute which had left the fate of the base up in the air and London looking increasingly isolated internationally, especially after Brexit cost it the support of the European Union.
However, there was no immediate comment from the Foreign Office on whether Chagos Islanders who were thrown off Diego Garcia in the 1960s will be allowed to return home under the deal, following decades of court battles.
Foreign Secretary David Lammy said: “This government inherited a situation where the long-term, secure operation of the Diego Garcia military base was under threat, with contested sovereignty and ongoing legal challenges.
“Today’s agreement secures this vital military base for the future. It will strengthen our role in safeguarding global security, shut down any possibility of the Indian Ocean being used as a dangerous illegal migration route to the UK, as well as guaranteeing our long-term relationship with Mauritius, a close Commonwealth partner.”
US President Joe Biden said: “I applaud the historic agreement and conclusion of the negotiations between the Republic of Mauritius and the United Kingdom on the status of the Chagos Archipelago.
“It is a clear demonstration that through diplomacy and partnership, countries can overcome long-standing historical challenges to reach peaceful and mutually beneficial outcomes.
“This agreement affirms Mauritian sovereignty over the Chagos Archipelago, while granting the United Kingdom the authority to exercise the sovereign rights of Mauritius with respect to Diego Garcia. “
In a phone call with Mr Jugnauth, Sir Keir “reiterated the importance of reaching this deal to protect the continued operation of the UK/US military base on Diego Garcia”, a Downing Street spokesperson said.
“He underscored his steadfast duty to national and global security which underpinned the political agreement reached today.”
The United States was keen to safeguard the future of Diego Garcia after rebuffs suffered by the UK in international courts which had ruled in favour of Mauritius.
The sovereignty negotiations were authorised by then Tory prime minister Liz Truss in October 2022 and announced by then foreign secretary James Cleverly.
But Mr Cleverly, who is now running to be Tory leader, retweeted a news article about the deal on Thursday to accuse the Labour Government of being “Weak, weak, weak!”
He said: “Labour lied to get into office. Said they’d be whiter than white, said they wouldn’t put up taxes, said they’d stand up to the EU, said that they (would) be patriotic. All lies!”
Former security minister Tom Tugendhat, who is also running to be Tory leader, said: “This is a shameful retreat undermining our security and leaving our allies exposed.”
He said the Foreign Office “has negotiated against Britain’s interest & it was disgraceful that these negotiations started under our watch”.
Critics of the talks, including Boris Johnson and former Royal Navy chief Lord West, had warned that a deal could allow China to claim a bridgehead in the Indian Ocean if Mauritius falls under Beijing’s sway.
Robert Jenrick, another Tory leadership hopeful, tweeted: “It’s taken three months for Starmer to surrender Britain’s strategic interests. This is a dangerous capitulation that will hand our territory to an ally of Beijing.”
However, analysts have stressed that Mauritius remains far closer to China’s arch-rival India - most people on the islands are of Indian descent, a legacy of British colonial rule - and that a deal was in the long-term interests of London and Washington.
