Critics argue that Sir Keir Starmer has caused a £30 billion setback for the nation by giving away the Chagos Islands.

The Prime Minister also faced criticism for committing an additional £1 billion over 25 years to Mauritius, an ally of China, as a part of the deal.

According to the agreement, Britain can lease the Diego Garcia airbase back, which will include a 24-nautical mile buffer zone, for a period of 99 years.

Tory leader Kemi Badenoch said: “Chagos has been ours since 1814. It hosts a vital military base.

“Surrendering it to Mauritius is an act of national self-harm.

“It leaves us more exposed to China, and ignores the will of the Chagossian people. And we’re paying billions to do so.”

The handover deal was signed yesterday afternoon, having survived a last-ditch legal challenge.

Tories put the cost at £30billion — but the PM says it is closer to a tenth of that.

He said it was vital for our security and pointed out it was supported by our major allies.

Insiders also say the Tories were prepared to sign a deal on worse terms without the exclusion zone.

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