The Diego Garcia military base will be banned from storing nuclear weapons if the Chagos deal goes ahead, the deputy prime minister of Mauritius has said.
Paul Berenger confirmed nuclear weapons could not be stored at the UK and US military site once the islands were handed over.
His comments throw into doubt Labour’s claims that the “full operational autonomy of the base” would be protected under Sir Keir Starmer’s deal.
It also creates a fresh diplomatic rift between the US and the UK over a deal Donald Trump last week branded an “act of great stupidity”.
Mauritius is a signatory to the African Nuclear weapon-free zone treaty, which prohibits “stockpiling, acquisition, testing, possession, control or stationing of nuclear weapons”.
Ministers have repeatedly claimed the agreement, known as the Pelindaba Treaty, would not have an impact on the operations at Diego Garcia.
However, The Telegraph has seen a recording of Mr Berenger, the Mauritian deputy prime minister, speaking in August about the impact of Britain’s handover of the base.
He said that while the temporary presence of nuclear weapons would be allowed, storing nuclear weapons on Diego Garcia would be banned.
He said: “The Pelindaba Treaty, this is not a new thing, it has been in place for years. It does not, unfortunately, ban the presence of nuclear (weapons), it prevents the storage.
“There is a difference between storage and transit.”
US bombers have been kept at Diego Garcia for decades as an Indian Ocean base – AFP
Dame Priti Patel, the shadow foreign secretary, said curtailing the storage of nuclear weapons on the base had “serious implications for our security and that of our allies”.
She told The Telegraph: “Ministers assured Parliament the deal would not interfere with the ‘full operational autonomy’ of the base. But the Mauritian government clearly takes a different view – and having dictated terms to our weak Prime Minister throughout this sorry process, they are unlikely to concede on this.
“This has serious implications for our security and that of our allies.”
She added: “These developments raise further doubts about whether our allies in the US will allow the surrender to go ahead. It’s little wonder they are so concerned when China, Russia and Iran – who have partnerships with Mauritius – have welcomed this deal.”
The US has conducted exercises in the region with B-52 jets, nuclear-capable bombers that could be blocked from using the base.
A US B-2 Spirit stealth bomber, a plane capable of deploying nuclear weapons, touched down on Diego Garcia for a “rapid refuelling mission” last year.
In 2022, the USS West Virginia, a ballistic missile submarine that has nuclear capabilities, stopped for a port visit.
The agreement, signed by the Prime Minister in May but not yet ratified, stalled on Friday when the Government was forced to pull the Bill.
A House of Lords debate on the legislation that was expected on Monday was delayed after the Tories said it could violate a 60-year-old treaty with the US.
