Donald Trump has reversed his stance on supporting the Chagos Islands deal, a decision reportedly driven by the United Kingdom's refusal to allow its airbases to be used for a pre-emptive US military strike on Iran. This latest shift in Trump's position was expressed on his Truth Social platform, where he criticized Keir Starmer's government for pursuing a deal to hand sovereignty of the Chagos Islands to Mauritius, while securing continued UK and US use of the crucial airbase on Diego Garcia.

Initially, Trump had described the Chagos agreement, which is backed by the US State Department, as the "best" deal Starmer could make. However, his recent post explicitly linked the deal to the potential for US military action against Iran, stating, "Should Iran decide not to make a Deal, it may be necessary for the United States to use Diego Garcia, and the Airfield located in Fairford, in order to eradicate a potential attack by a highly unstable and dangerous Regime."

The core of the disagreement lies in the UK's interpretation of international law. US military bases in the UK, such as RAF Fairford in Gloucestershire (home to US B-2 bombers in Europe) and Diego Garcia in the Indian Ocean, can only be used for military operations if the UK government agrees and deems them legal. A pre-emptive strike on Iran, particularly without an actual or imminent attack, would likely be considered a breach of international law by the UK. This adherence to legal precedent, which traces back to discussions before the Iraq war regarding self-defence and UN resolutions, has been cited by UK government sources as the reason for Trump's renewed opposition to the Chagos plan.

The White House has reportedly been drawing up detailed military plans for an attack on Iran, involving both Diego Garcia and RAF Fairford. Defence officials are said to have briefed Trump that the US would be ready to commence operations soon, following a significant build-up of American aircraft and ships in the Middle East, including around 50 extra fighting jets and air-to-air refuelling tankers. The deployment of a second aircraft carrier strike group, the USS Gerald R. Ford, to the eastern Mediterranean further underscores these preparations, with potential roles including protecting Israel or launching strikes against Iran.

Potential US military options against Iran include attacking nuclear facilities—which Trump previously claimed were "obliterated" during Operation Midnight Hammer—or even triggering regime change from the air. Such a campaign might involve attempts to assassinate Iran's supreme leader, Ali Khamenei, and senior officers of the Islamic Revolutionary Guard Corps, aiming to destabilize the regime and potentially encourage popular demonstrations. Sascha Bruchmann, a research fellow at the International Institute for Strategic Studies, suggested strikes could target communications to disrupt the regime's organization, hoping the mainstream Iranian army might side with the people.

Despite two rounds of US-Iran negotiations in Geneva making limited progress, Trump has reportedly been briefed on his military options amidst the largest assembly of air power in the region since the 2003 Iraq invasion. Preparations for potential joint strikes have also begun in Israel, with its military having over 200 combat aircraft. Trump had previously held off on striking Iran after setting red lines over the killing of peaceful protesters and mass executions, while re-engaging Tehran in nuclear talks.

In response to escalating tensions, Iran has been conducting military drills with Russia in the Gulf of Oman and the Indian Ocean, days after temporarily closing parts of the Strait of Hormuz and firing cruise missiles. These drills, aimed at "upgrading operational coordination" and enhancing "security and sustainable maritime interactions," serve as a stark warning of potential economic fallout. Amidst these developments, Polish Prime Prime Minister Donald Tusk urged all Polish citizens to evacuate Iran immediately, warning that the option to leave might soon become impossible.

The political fallout in the UK continues, with the Chagos agreement bill facing delays in the House of Lords due to uncertainty over the US position. The Conservatives are actively opposing the plan, with Shadow Foreign Secretary Priti Patel stating the deal is "now dead in the water" without American support. A former government official expressed concern that the deal, which is forecasted to cost the taxpayer £35 billion and includes leasing back Diego Garcia for 99 years at an average cost of £101 million annually, might be "scuppered" if not passed before the current parliamentary session ends in May. Downing Street, while supporting the ongoing political process between the US and Iran and emphasizing regional security, hopes Trump will once again change his mind regarding the Chagos plan.