Britain hands Chagos Islands, home of secretive US military base, over to Mauritius

LONDON — The U.K. agreed to pass sovereignty of the disputed Chagos Islands to Mauritius after decades of campaigning — with one big caveat.

U.K. Prime Minister Keir Starmer and his Mauritian counterpart Pravind Jugnauth hailed a “seminal moment” Thursday as a political agreement was struck on the future of the islands, which have been called Britain’s last African colony and are home to a crucial U.S. and U.K. military base in the Indian Ocean.

Mauritius’ government has long argued it was forced to give the Chagos Islands away in return for its own independence from Britain in 1968. More than 1,000 islanders were forcibly removed at the request of the U.S., with some repeatedly taking the U.K. government to court.

The chain of islands in the Indian Ocean includes Diego Garcia — used by the U.S. government as a base for its navy ships and long-range bomber aircraft.

Under the agreement struck Thursday, Diego Garcia itself will remain under U.K. and U.S. jurisdiction for at least the next 99 years to allow the base to keep running.

But the joint statement says the deal “will address wrongs of the past and demonstrate the commitment of both parties to support the welfare of Chagossians.”

Mauritius will implement a program of resettlement on all islands apart from Diego Garcia, the agreement promises, while the U.K. will provide a package of financial support for infrastructure projects to boost economic development on the islands.

Britain only recently acknowledged Mauritius had any claim to the islands, and the political agreement — subject to a formal treaty — comes after years of negotiations that began under the last Conservative administration.

A 2019 advisory opinion from the International Court of Justice, which adjudicates on disputes between nations, found that the detachment of the Chagos Islands from Mauritius was “not based on the free and genuine expression of the will of the people concerned.”

It said the U.K. was “under an obligation to bring to an end its administration of the Chagos Archipelago as rapidly as possible.”

‘Deeply regrettable’

The move has already sparked some political controversy in the U.K., with prominent Conservatives arguing that the ICJ “had no jurisdiction to challenge the U.K.’s sovereignty” over the islands.

 Shadow Security Minister Tom Tugendhat, who is running for the Tory leadership, argued that the move “compromises both our national security and the stability of the region.” He accused Labour of a “total failure of leadership and strategic vision.”

Conservative former Defense Secretary Grant Shapps called it a “weak and deeply regrettable act.”

But there was swift backing from the United States.

President Joe Biden said in a statement that the deal was “a clear demonstration that through diplomacy and partnership, countries can overcome long-standing historical challenges to reach peaceful and mutually beneficial outcomes.”

A Downing Street spokesperson said Starmer had “reiterated the importance of reaching this deal to protect the continued operation of the U.K./U.S. military base on Diego Garcia.

“He underscored his steadfast duty to national and global security which underpinned the political agreement reached today.”

Both the U.K. and Mauritius said Thursday that they want to complete the treaty underpinning the deal “as quickly as possible.”

This story has been updated with further reporting.