The United Kingdom government defended its agreement to cede the Chagos Islands to Mauritius while leasing back a key military base, following criticism from former U.S. President Donald Trump. Trump, in a post on his Truth Social platform, described the deal as an "act of great stupidity" and "total weakness," despite previous indications of support from him and senior U.S. officials.

The UK government responded by asserting that it would "never compromise on our national security." The prime minister's spokesperson stated that the U.S. continues to support the agreement.

The deal, signed in May and valued at £3.4 billion ($4.6 billion), allows the UK to retain control of a UK-US military base on Diego Garcia, the largest of the Chagos Islands. Trump's post specifically called out the plan to "give away the Island of Diego Garcia, the site of a vital U.S. Military Base, to Mauritius, and to do so FOR NO REASON WHATSOEVER." He also alluded to concerns about China's potential influence in the region.

The Chagos Islands have been the subject of a long-standing sovereignty dispute between the UK and Mauritius. Mauritius argues that the islands were illegally separated from its territory by the UK in 1965, prior to Mauritian independence in 1968. The UK has maintained control of the archipelago, which includes Diego Garcia, a strategically important location for military operations.

The International Court of Justice ruled in 2019 that the UK should relinquish control of the Chagos Islands, a decision the UK has acknowledged but not fully implemented. The current agreement with Mauritius aims to address this ruling while ensuring the continued operation of the military base.

The UK government maintains that the agreement with Mauritius safeguards the operation of the joint UK-US military facility on Diego Garcia, which is considered vital for regional security. The base has been used for various military operations, including during the Gulf War and the conflicts in Afghanistan and Iraq. The agreement includes provisions for environmental protection and potential future Mauritian access to the islands, while ensuring the continued operation of the military base.