Britain should "stand firm" and not cede control of the Chagos Island to Mauritius as it would put the country's strategic interests in danger, a new report says.
Earlier this year, Foreign Secretary James Cleverly announced that the UK was entering into negotiations with Mauritius about the future of the British Indian Ocean Territory.
The UN’s highest court, the International Court of Justice, previously ruled that the UK’s administration of the territory is “unlawful” and must end after two centuries of British control.
But the Conservative government said that whatever the outcome of the talks between the two countries, a joint UK-US military base on Diego Garcia, one of those in the cluster of Indian Ocean islands that make up the Chagos Islands, will continue to be operated by allies.
The new Policy Exchange report says that Britain should not relinquish sovereignty over the islands in return for "an unenforceable promise by a third country that the military base at Diego Garcia will be allowed to continue to operate in the future".
In addition, the report says the UK should only hand over the territory after consulting Chagossians, with any future deal allowing provision for "continuing free association with the UK".
The authors argue that the government should revert to "the longstanding, cross-party position that the UK enjoys sovereignty over the Chagos Islands".
Richard Ekins, head of Policy Exchange’s Judicial Power Project, says the British government should halt negotiating a treaty of cession with Mauritius, and should retain Diego Garcia at all costs.
The report is backed by Admiral the Lord West of Spithead, who argues that ceding control of the territory “... would put our strategic interests – and the interests of our closest allies – in danger, while also recklessly undermining fundamental principles of international law".
Lord West argues that the Chinese are pushing Mauritius to claim Diego Garcia and that China wants access to and control of the port and airfield facilities.
"The UK must stand firm", he says. "With the return of great power competition, and an increasingly aggressive Chinese regime active throughout the region, the territory is of fundamental importance to UK security and foreign policy."
Any move to cede Chagos would "a colossal mistake" and one which opposition parties in parliament would also be "complicit in".
Mr Ekins says the government should recognise that ceding the Chagos Islands "would be an irresponsible act, which would put our strategic interests – and the interests of our closest allies – in danger, while also recklessly undermining fundamental principles of international law.”