Keir Starmer has been forced into an embarrassing climbdown after U.S. president Donald Trump tore into Britain’s plan to give away the Chagos Islands, triggering legal alarms and exposing fresh cracks in the UK’s security policy.
The British prime minister quietly pulled legislation that would have handed the Indian Ocean archipelago to Mauritius, just days before it was due to be debated in parliament. The retreat followed blunt warnings that the deal could breach a binding UK–U.S. defence treaty—and a withering public attack from the White House.
Trump did not mince his words. Posting on Truth Social, the U.S. president called the proposed handover “an act of great stupidity,” warning that surrendering strategically vital territory weakened Western security at a time of growing global tension. His intervention landed heavily in London, where officials were already struggling to justify the plan.
At the heart of the row is Diego Garcia, a remote island that hosts one of the most important military bases in the world. Built in the 1970s, the base has been used by U.S. and British forces to project power across the Middle East, Africa, and Asia. It is widely seen in Washington as irreplaceable.
Under Starmer’s proposal, Britain would give up sovereignty over the Chagos Islands but lease the base back from Mauritius—effectively paying to retain access to territory it currently controls. Critics have dismissed the arrangement as strategically absurd and legally dangerous.
Those legal concerns proved decisive. A UK–U.S. treaty signed in 1966 explicitly states that the Chagos Islands “shall remain under United Kingdom sovereignty.” Opposition lawmakers warned that ratifying the deal without first rewriting that treaty would place Britain in breach of international law and undermine the legal foundations of the U.S. military presence.
Ministers admitted that talks with Washington to update the treaty were still unfinished. Despite that, Starmer’s government had been pushing ahead, insisting the deal was necessary for “security reasons” and to draw a line under decades of legal disputes with Mauritius.
Starmer has leaned heavily on a 2019 advisory opinion from the International Court of Justice, which suggested Britain should relinquish control of the islands. But the ruling is non-binding and carries no force over bilateral defence treaties—a point repeatedly highlighted by critics.
The Chagos controversy is also entangled with unresolved claims by displaced islanders, whose mistreatment decades ago remains a stain on Britain’s record. Opponents argue that handing the territory to Mauritius does little to address those injustices while creating new strategic risks.
