Britain hands over control of Chagos Islands to Mauritius

The British government signed a deal on Thursday to transfer the Chagos Islands to Mauritius after a last-minute injunction following a challenge in court by two Chagossian women was lifted by a judge.

UK Prime Minister Keir Starmer said the decision to hand over sovereignty of the archipelago to Mauritius ensures the future of a US-UK military base.

"This is absolutely vital for our defense and intelligence, and therefore, for the safety and security of the British people. The full assessment of why this is so important is highly classified," Starmer said at a press conference on Thursday.

The Indian Ocean archipelago is home to a strategically important naval and bomber base on the largest of the islands, Diego Garcia. Under the agreement, the UK will pay Mauritius 101 million pounds per year to lease back the base for at least 99 years.

The signing was delayed for several hours after a UK judge imposed a last-minute injunction blocking the transfer. That was later lifted by another judge.

A history of contested claims to the archipelago

One of the last remnants of the British Empire, the Chagos Islands have been under British control since 1814. Britain split the islands away from Mauritius, a former British colony, in 1965, three years before Mauritius gained independence.

Britain evicted as many as 2,000 people from the islands in the 1960s and 1970s so the US military could build the Diego Garcia base, which has supported US military operations from Vietnam to Iraq and Afghanistan.

Displaced Chagossians fought unsuccessfully in UK courts for years for the right to go home. Under the deal, a resettlement fund would be created to help displaced islanders move back to the islands, apart from Diego Garcia. Details of any such measures remain unclear.

Mauritius has long contested Britain’s claim to the archipelago and in recent years the United Nations and its top court have urged Britain to return the Chagos to Mauritius, around 2,100 kilometers southwest of the islands. In a non-binding 2019 opinion, the International Court of Justice ruled that the UK had unlawfully carved up Mauritius when it agreed to end colonial rule in the late 1960s.

The British government says those rulings put the future of the Diego Garcia base, vital to UK security, at stake.

Through the deal, London hopes to maintain the military base functional for the future.

Critics of the deal have however shown scepticism regarding the price tag of the agreement and Mauritius' heavy dependence on Chinese imports, which has raised concerns for national security.

Negotiations on handing the islands to Mauritius began in 2022 under the previous Conservative government and resumed after Starmer's Labour Party was elected in July.