The United States has officially backed the United Kingdom’s agreement to transfer sovereignty of the Chagos Islands to Mauritius while leasing back the strategically vital joint military base on Diego Garcia, Downing Street confirmed to the BBC on Thursday. The announcement comes after US President Donald Trump signaled his approval of the arrangement, describing Prime Minister Sir Keir Starmer’s agreement as “the best he could make.” This endorsement is viewed as crucial in securing the continued operation of the base, which serves as a key hub for joint UK-US military operations in the Indian Ocean. Downing Street emphasized that both leaders recognized the importance of maintaining security at the base while respecting the sovereignty transfer, underscoring the deal’s strategic and diplomatic significance.
The announcement follows a period of tension between the UK and the US, stemming from Trump’s previous criticisms of the agreement. Just weeks ago, the former president branded the deal an “act of great stupidity,” sparking concerns within Whitehall that the United States might withdraw support for the arrangement. His comments prompted additional discussions between UK and US officials to clarify the position of the US government and ensure ongoing support for the agreement. The controversy had fueled uncertainty over the future of the joint military base, prompting rapid diplomatic engagement to maintain the continuity of US-UK operations on Diego Garcia.
The Chagos Islands deal, originally announced last year, involves the UK formally transferring sovereignty of the islands to Mauritius while simultaneously securing a leaseback of the joint military base on Diego Garcia for an initial period of 99 years. The base is of significant strategic importance, serving as a central hub for American and British military activity in the Indian Ocean region, including operations related to surveillance, logistics, and rapid deployment. The leaseback arrangement ensures that while sovereignty is transferred, the operational capabilities of the base remain protected, allowing continued collaboration between the two allies without disruption.
During a conversation on Thursday, Sir Keir Starmer and Donald Trump reportedly agreed on the continued importance of the deal in maintaining the security of the base. Trump, in a post on his Truth Social platform, described discussions with Starmer as “very productive,” adding that the agreement “is, according to many, the best he could make.” He also emphasized that if the lease deal were ever threatened or disrupted in the future, the United States reserves the right to “militarily secure and reinforce the American presence in Diego Garcia.” White House Press Secretary Karoline Leavitt later reiterated that Trump fully understands and supports Starmer’s position while emphasizing the US’s right to safeguard its operational assets.
US Ambassador to the UK, Warren Stephens, echoed Trump’s position, acknowledging that while the “ideal” outcome for the US would have been for the UK not to transfer sovereignty, the deal represented the “best on the table for successive UK governments.” Stephens further stressed that the United States retains the right to maintain and, if necessary, reinforce security interests on Diego Garcia, aligning with Trump’s previous statements. This dual approach seeks to balance recognition of Mauritius’s sovereignty with the operational requirements of the joint military base, ensuring long-term strategic stability for both nations.
The parliamentary process in the UK has also been impacted by the controversy surrounding the deal. A draft law to ratify the Chagos Islands agreement is currently making its way through Parliament but has faced delays following Trump’s public criticism. Sir Keir Starmer has maintained that the deal is necessary to protect the continued operation of the base, particularly in light of past legal challenges from Mauritius disputing British sovereignty over the islands. The draft law is now under scrutiny amid opposition from Conservative and Reform UK lawmakers, who argue that the arrangement undermines national security due to Mauritius’s perceived connections with China.
Conservative Shadow Foreign Secretary Dame Priti Patel described the leaseback and sovereignty transfer as “an appalling surrender,” asserting that Trump’s latest statements merely confirm the weaknesses inherent in the agreement. She added that the Conservative Party remains firmly opposed to the deal and will continue to challenge it through parliamentary and public channels. Reform UK has also expressed concerns, framing the arrangement as compromising the United Kingdom’s strategic position while raising questions about long-term security guarantees. Despite these criticisms, the government has maintained that the deal is essential for the operational continuity of the base.
The controversy surrounding the Chagos Islands deal cannot be divorced from the wider context of Trump’s Greenland row. In prior statements, the former president linked the deal to broader national security concerns, suggesting that territorial concessions could weaken US and allied strategic interests. His public criticism of the Chagos agreement, coupled with his remarks on Greenland, fueled speculation about the stability of US-UK defense cooperation and prompted intensive diplomatic engagement to reassure all parties involved that the agreement would remain intact. Downing Street officials subsequently engaged in direct talks with the White House to reaffirm American support and clarify the operational implications for Diego Garcia.
Following these high-level discussions, Downing Street confirmed that both leaders had agreed to work closely on the implementation of the Chagos Islands deal. While the United States continues to reserve the right to protect its assets on Diego Garcia, both governments underscored their commitment to honoring the leaseback arrangement and ensuring the base’s uninterrupted operation. The agreement highlights a pragmatic approach to balancing sovereignty concerns with strategic military interests, preserving US-UK operational capabilities while recognizing Mauritius’s territorial rights.
The implications of US support for the Chagos Islands deal are significant for future diplomatic and security relations. Continued American endorsement ensures that the joint military base at Diego Garcia remains fully operational and strategically secure, a key consideration for UK defense planning in the Indian Ocean region. Simultaneously, the transfer of sovereignty to Mauritius represents a diplomatic milestone, resolving longstanding disputes over the islands while creating a framework for cooperative engagement. As parliamentary ratification proceeds and implementation begins, both the UK and US have signaled their intent to safeguard military capabilities and maintain strong bilateral relations with Mauritius, ensuring a balance between operational security and respect for international sovereignty.