Trump says Starmer is making a “big mistake” over Chagos Islands deal

Former U.S. President criticises UK PM over sovereignty transfer to Mauritius

He urged the UK not to give away Diego Garcia, the site of the key joint US-UK military base in the Indian Ocean.

In a post on Truth Social on 18 Feb 2026, Donald Trump warned Sir Keir Starmer that the UK’s plan to hand over the Chagos Islands to Mauritius is a “big mistake.”

What Happened

Trump claims that losing control of Diego Garcia weakens strategic defence.

Why Trump Objects

He argues the base could be needed for military operations such as countering threats from Iran.

He described long-term lease deals as “tenuous” and warned Starsmer against relinquishing permanent control.

The Deal Context

– The UK will transfer sovereignty of the Chagos Archipelago to Mauritius. – The UK will lease Diego Garcia for the next ~100 years to maintain the US-UK base. – This lease carries multi-billion-pound commitments over decades.

The deal was agreed in May 2025:

Trump’s latest statements were framed as his own policy.

Notably, Trump’s criticism contradicts the U.S. State Department, which had said it supported the UK-Mauritius agreement just a day earlier.

U.S. Govt Contradictions

• Some Conservatives called it an “utter humiliation” for Starmer. • Reform UK politicians echoed criticism of the deal. The UK government defended the agreement as the only way to secure the long-term future of the base.

Reactions in UK Politics

UK opposition figures and critics seized on Trump’s comments:

Key Takeaways

Main points:

– Trump calls Starmer’s move a “big mistake.” – Disagreement even with parts of the U.S. govt. • Strategic focus is on Diego Garcia base. – UK maintains the base through a long lease despite sovereignty transfer. – Domestic and geopolitical tensions continue.