THE UK has agreed to hand over its last African colony to Mauritius, ending years of dispute.

The sovereignty of the remote Chagos Islands in the Indian Ocean will be handed to Mauritius after more than half a century in return for securing the long-term future of a strategically important military base.

The UK expelled the Chagossians in the 1960s and 1970s in what has been described as a crime against humanity, when it retained possession of what it called the British Indian Ocean Territory, or BIOT, after Mauritius gained independence in 1968.

The agreement follows rounds of negotiations that began in 2022 after Mauritian arguments for sovereignty were recognised by the International Court of Justice (ICJ), the UN general assembly and the International Tribunal of the Law of the Sea (Itlos) in 2019 and 2021.

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Britain was found to have unlawfully separated the Chagos Islands from Mauritius before granting independence in 1968.

The UK initially defied UN votes and court judgments demanding it return the islands, emphasising that the ICJ ruling was only an “advisory opinion”. An attempt to halt the negotiations, on the basis the Chagossians were not consulted or involved, failed.

The deal will include the UK handing over the tropical atoll of Diego Garcia, used by the US government as a military base for its navy ships and long-range bomber aircraft.

But the US-UK base will remain on Diego Garcia – a key factor enabling the deal to go forward.

The deal is still subject to finalisation of a treaty but both sides have vowed to complete this as quickly as possible.

"Following two years of negotiation, this is a seminal moment in our relationship and a demonstration of our enduring commitment to the peaceful resolution of disputes and the rule of law," the statement from Prime Minister Keir Starmer (above) and Mauritius Prime Minister Pravind Jugnauth read.

The leaders also said "both our countries are committed to the need...to ensure the long-term, secure and effective operation of the existing base on Diego Garcia which plays a vital role in regional and global security."

Both parties said the treaty would "address wrongs of the past and demonstrate the commitment of both parties to support the welfare of Chagossians".

The deal has angered the Conservatives with leadership hopeful Robert Jenrick saying: “It’s taken three months for Starmer to surrender Britain’s strategic interests.

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“This is a dangerous capitulation that will hand our territory to an ally of Beijing.”

James Cleverly, another Tory leadership contender, said: “Weak, weak, weak! 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 be patriotic. All lies!”

Another leadership hopeful Tom Tugendhat added: “This is a shameful retreat undermining our security and leaving our allies exposed.”

The Foreign Office said the agreement is supported by the US and means the status of the base will be undisputed and legally secure.