Keir Starmer says the deal - which involves leasing the Diego Garcia base for 99 years, with the option of another 40 - is in the UK's national interest.

Britain signed an agreement Thursday to hand sovereignty over the contested Chagos Islands to Mauritius, a move the government says ensures the future of a US-UK military base that is vital to British security.

The UK agreed to cede an Indian Ocean archipelago to Mauritius while retaining control of a strategic military base on one of the islands, ending a long-running negotiation that had become a point of controversy for British premier Keir Starmer.