WASHINGTON - US President Donald Trump said on Wednesday that Britain's Prime Minister Keir Starmer was making a big mistake by entering into a lease of the U.S.-UK air base on Diego Garcia.

"Prime Minister Starmer is losing control of this important Island by claims of entities never known of before," Trump said in a post on Truth Social.

Trump also said it may be necessary for the U.S. to use Diego Garcia, and an airfield located in Fairford, in order to "eradicate a potential attack" by Iran if Tehran decides not to make a deal resolving their longstanding nuclear dispute.

Under a 2025 agreement, Britain will transfer sovereignty of the Chagos Islands to Mauritius while retaining control of the strategically important U.S.-UK air base on Diego Garcia under a 99-year lease. REUTERS