UK Examines Whether Trump Has Power to Derail Chagos Deal

The UK government is seeking to determine whether Donald Trump has the power to derail its plans to hand over sovereignty of a strategically vital island to Mauritius, after the US president called into question a deal he previously backed.

Ministers are also trying to establish if the US administration intends to veto the deal over the Chagos Islands, according to a person familiar with the matter, who requested anonymity speaking about a diplomatically sensitive topic. They said that if the US does change its long-held position, it would likely be enough to unravel the agreement.

Under the deal brokered by Keir Starmer’s government, Britain will lease back a joint US-UK military base on Diego Garcia from Mauritius for 99 years. After supporting the agreement last year, Trump last week called it an “act of total weakness” and “great stupidity.” That’s despite his own previous support and Secretary of State Marco Rubio’s description of the deal as a “monumental achievement.” 

The fallout over the Chagos islands highlights the tricky balancing act Starmer faces as he seeks to honor an agreement reached with Mauritius after two years of negotiations without angering Britain’s most important ally. Starmer’s administration has said the deal is key to enable the continued legal use by the UK and US of what is a vitally strategic air base.

Trump Flips Position to Attack UK’s Starmer Over Chagos Deal

Conversations between UK and US officials have taken place in recent days in an attempt to ease the White House’s concerns. Even so, Starmer’s spokesman, Geraint Ellis, on Wednesday couldn’t say whether the US has the power to unravel the deal. 

“The UK and US have worked closely together in developing the treaty, which will secure the joint base on Diego Garcia that’s vital to our national security,” he said. “We continue to work closely with the US to ensure that the necessary arrangements are in place for the future operations of the base.”

The State Department declined to comment, pointing to Trump’s Truth Social post.

The Times on Wednesday reported that ministers are increasingly concerned that Trump could pull the deal and that Starmer did not raise the issue during a call with the President on Saturday.

Starmer, however, said he’s discussed Chagos with Trump a number of times, and the issue has been raised with the White House as recently as this week. 

“When the Trump administration came in, we paused for three months to give them time to consider the Chagos deal, which they did at agency level,” he told reporters on his way to China. “Once they’d done that, they were very clear in the pronouncements about the fact that they supported the deal.”

Starmer last week told the House of Commons that Trump’s volte-face over Chagos “expressly intended to put pressure on me to yield on my principles” over Greenland after the British premier had criticized Trump’s attempts to take control of the semi-autonomous Danish territory.

Britain is now seeking to ease US concerns over Diego Garcia without drawing the issue back onto Trump’s radar while he’s distracted by Iran and domestic controversies. 

UK opposition parties with links to the White House are seeking to do the reverse. Conservative leader Kemi Badenoch discussed her opposition to the Chagos deal with House Speaker Mike Johnson the evening before Trump’s social media post. She’s also discussed it with US ambassador Warren Stephens, her office said. Trump ally Nigel Farage, leader of the Reform UK Party, meanwhile, discussed Diego Garcia with US Treasury Secretary Scott Bessent over dinner at the World Economic Forum in Davos earlier this month.

While the UK has already signed the treaty with Mauritius, a bill to implement it is yet to complete its passage through Parliament, with ministers disputing several amendments passed in the Lords. 

Last week, the government postponed a Lords debate after the Tories tabled an amendment to ensure the deal doesn’t breach a 1966 UK-US treaty, which confirms British sovereignty of the islands. The government accused the Tories “irresponsible” and “reckless” behavior and said they would reschedule the debate soon.

However, Marc Weller, Director of Chatham House’s international law program, said in a blog post this week that the 1966 agreement “was no oath of eternal UK sovereignty over the Chagos Archipelago, or Diego Garcia” and that international law recognizes that circumstances can change.

The government confirmed on Monday that updating that UK-US agreement was a pre-requisite to enable it to ratify the Chagos Treaty. 

The UK has “made excellent progress toward finalizing an updated UK-US agreement,” foreign office minister Stephen Doughty told the House of Commons on Monday. He said it wasn’t unusual as it has been updated five times previously, the latest in 1999.

“We remain engaged with the US on a daily basis on matters relating to our national security and we will continue to engage with them on this important matter,” he said, adding that Britain aims to “allay any concerns, as we have done throughout this process.”

The Chagos Islands and the Diego Garcia base are almost 2,000 miles from the coast of East Africa. The US and UK military facility there allows those nations to more easily carry out missions from the Middle East to Asia. 

Britain’s concerns aren’t isolated. “We will see what happens,” Mauritius’ attorney general, Gavin Glover, told private radio on Saturday. “We are close to the goal. Let us dare to hope that we will be able to complete the treaty in the forthcoming weeks.”

With assistance from Alex Wickham, Kamlesh Bhuckory, Lucy White, Will Standring and Eric Martin.

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