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The UK is reviewing its deal to hand over the Chagos Islands to Mauritius, the defence secretary has said, after US President Donald Trump called it "terrible" at the UN General Assembly.

Defence Secretary Wes Streeting said "we have to" review the deal "because the United States doesn't support it".

The original agreement would see the UK cede sovereignty of the territory to Mauritius and pay an average of ยฃ101m ($136m) per year to lease back a joint UK-US military base there, prized for its strategic location in the Indian Ocean.

The BBC's diplomatic correspondent Caroline Hawley looks at why the government's agreement with Mauritius has stalled.

Read more about Donald Trump's comments on Chagos Islands.

Watch: Why is the UK reviewing its Chagos Islands deal? Video, 00:01:21Watch: Why is the UK reviewing its Chagos Islands deal?

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