Diego Garcia to remain key base as UK transfers Chagos Islands to Mauritius

The UK has agreed to transfer sovereignty of the Chagos Islands to Mauritius after more than 50 years of control, but Diego Garcia, the archipelago’s most strategically vital asset, will remain a crucial military base for both the United States and the UK.

Diego Garcia, a tropical atoll in the Indian Ocean, has been a significant hub for US naval and air operations.

The base, which supports US Navy supply ships and long-range bombers like the B1-B Lancer, provides a secure location from which operations can reach across the Middle East.

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The US base there is sizeable and considered highly important to maintaining regional stability.

Meanwhile, a small UK detachment, reportedly around 40 personnel, provides police and customs services on the island.

Despite the handover of the wider Chagos Islands, the US-UK military presence on Diego Garcia will continue under a new framework.

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."

And US President Joe Biden emphasised Diego Garcia's importance in balancing both sovereignty and strategic interests.

"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," he explained.

The agreement, reached after years of negotiations, is seen as a diplomatic breakthrough, maintaining the strategic value of Diego Garcia as a military outpost while formally recognising Mauritian sovereignty over the Chagos Islands.

The base’s continued operation comes at a time of growing geopolitical competition between Western powers, India and China, reinforcing its importance in the Indian Ocean.

Mauritius will also be allowed to start a resettlement programme on the Chagos Islands, but this will not include Diego Garcia.