Nigel Farage has claimed Donald Trump’s incoming administration has “outright hostility” towards the UK’s deal to hand the Chagos Islands over to Mauritius.

Labour arranged to give up sovereignty over the archipelago, which contains a UK-US military base, last month, after holding it for more than 50 years.

It was praised by outgoing US president Joe Biden at the time as a “historic agreement”.

But, according to Reform UK leader and close Trump ally Farage, the next administration has a different take.

In the Commons on Wednesday afternoon, Farage said: “I can assure you, having been in America last week, knowing also the incoming defence secretary [Pete Hegseth] very well, there is outright hostility to this deal.

“Whatever is said about a lease agreement, as we saw with Hong Kong, these agreements can very, very easily be broken.

“Diego Garcia [where the military base is] was described to me by a senior Trump adviser as the most important island on the planet as far as America was concerned.”

Farage claimed: “There is no basis for this agreement to continue what it is, and if you do, you will be at conflict with a country without which we would be defenceless.”

He added that there was “no legal reason” why the UK had to give sovereignty of Chagos to Mauritius, as the International Court of Justice’s ruling – saying the islands should change hands – was only advisory.

The Reform leader also claimed that Chagossian people “do not wish to live under Mauritian rule”.

When the deal was first struck, critics said it was a strategic error because of the islands’ location in the Indian Ocean.

They expressed fears it would put other contested territories like Gibraltar and Falkland Islands under threat.

The Independent also reported on Wednesday that the Trump transition team has requested legal advice from the Pentagon over the agreement.

US government sources allegedly told the newspaper Trump might veto the deal – not to set to take place until after the president-elect’s inauguration – over global security fears.

However, Foreign Office minister Stephen Doughty told Farage in the Commons that he “fundamentally disagrees” with his claims about US attitudes to the deal.

He said: “This government inherited a situation where the long-term secure operation of this crucial military base [Diego Garcia] was under threat.

“International courts were reaching judgments. International organisations were taking steps not to undermine Mauritian sovereignty, and this threatened the secure and effective operation of the base.

“And, in the absence of a negotiated solution, a legally binding decision against the UK seemed inevitable. This would have threatened the secure and effective operation of the base and that was not sustainable.”

He added that when the Trump administration have been fully briefed, he was “confident that the details of this arrangement will allay any concerns”.