Did Iran launch missiles at US-UK base on Diego Garcia? Here’s what to know

EXPLAINERUK condemns what it says is Iranian attack on airbase in Indian Ocean, but Tehran denies it carried out the launches.A US Air Force B-1B bomber takes off from the Diego Garcia military base on a mission in Afghanistan on October 7, 2001 [Handout/US Department of Defense via AFP]Published On 22 Mar 2026The United Kingdom has slammed “reckless Iranian threats” after missiles targeted a joint United States-UK military base located on the Indian Ocean island of Diego Garcia.An Iranian official, however, has denied the allegations that it was behind the launch of what US media outlets said were two ballistic missiles.Recommended Stories list of 4 itemslist 1 of 4Iran war: What’s happening on day 23 of US-Israel attacks?list 2 of 4Why the world should worry about Israel’s nuclear doctrinelist 3 of 4‘The United States doesn’t even pretend to be within international law’list 4 of 4Photos: Aftermath of Iranian missile strikes near Israel’s nuclear facilityend of listThe US has not officially commented on the firing of the missiles at Diego Garcia, which is 4,000km (2,500 miles) from Iran.The incident was reported after the US and Israel launched a war on Iran on February 28, one of whose goals, they said, was to degrade Iran’s nuclear and missile programmes.Tehran has maintained its nuclear programme is for civilian purposes. The United Nations nuclear watchdog and US intelligence chief Tulsi Gabbard said Iran was not on the verge of making nuclear bombs. Contrary assertions were invoked to launch the current war.Here is what we know about the alleged missile launch and what it means for the war:Six US B-2 bombers and six Stratotanker refuelling planes are seen from a satellite on Diego Garcia island on April 2, 2025 [Handout/Planet Labs via AFP)Was Diego Garcia airbase targeted by Iran?An attempted targeting of the Diego Garcia joint military base by ballistic missiles reportedly happened between Thursday night and Friday morning, according to US media.The Wall Street Journal and CNN reported that one of the missiles failed mid-flight while the other was hit by a US interceptor fired from a warship.It is said to have happened just hours before UK ministers were to assemble in London to discuss the Iran war. At the meeting, the UK agreed to let the US use its military bases for collective self-defence, such as hitting Iranian missile sites used in attacks on shipping in the Strait of Hormuz.UK officials did not provide any details of the attempted Diego Garcia strikes.Muhanad Seloom, lecturer at the Doha Institute for Graduate Studies, told Al Jazeera that the reported Iranian attack “changes the calculus” of the war for the US.“These missiles to Diego Garcia mean Iran has 4,000km-plus ballistic missiles, and that hasn’t been revealed before. All reports before that said Iran had a 2,000km [1,240-mile] range and not beyond that,” Seloom said.“If you reverse the direction of these missiles, then they could reach London, so that changes the calculus not only for the US and its justification for the war but also for a reluctant London and European Union to join the war.”A senior Iranian official told Al Jazeera that Tehran is not responsible for the alleged missile launch.Earlier this month in an interview with the US broadcaster NBC, Iranian Foreign Minister Abbas Araghchi rejected US President Donald Trump’s assertion that Tehran had developed missiles capable of reaching US territory.“You know, we have capability to produce missiles, but we have intentionally limited ourselves to below 2,000km of range because we don’t want to be felt as a threat by anybody else in the world,” Araghchi said on March 8.Aniseh Bassiri Tabrizi, an associate fellow in the Middle East and North Africa Programme at Chatham House, said Iranian denials regarding attacks depend on their nature and their aftermath.“I think the denial is different from the steps that Iran is taking on other fronts. Only a couple of instances when Iran denied an attack is when the strikes hit civilian infrastructure or some gas plants rather,” he told Al Jazeera.Iran has denied attacks that Tabrizi believes would likely “provoke further action or retaliation potentially”. “It also constitutes a new crossing of a red line that it hasn’t crossed until now,” he said.The targeting of the Diego Garcia airbase “is particularly sensitive because we know the distance of the missiles shot was more, much more than the 2,000km which Iran has previously said it kept its missiles to”.“It signals the Iranian capability to reach far beyond 2,000km, and therefore, is something that is likely to provoke further concern and, therefore, response particularly from the UK but also from other countries,” he said.US President Donald Trump, left, and British Prime Minister Keir Starmer meet during a state visit by Trump on September 18, 2025, in Aylesbury, Britain [Leon Neal/Pool via Reuters]What has the UK said?Foreign Secretary Yvette Cooper condemned “reckless” attacks by Iran after London insisted it would not be drawn into a wider conflict in the Middle East.“Our approach to this conflict has been the same throughout. We were not and continue not to be involved in offensive action, and we’ve taken a different view from the US and Israel on this,” she said.Cooper said Royal Air Force jets and other military assets were defending “our people and personnel in the region”. She added that any action to protect the Strait of Hormuz would amount to “collective self-defence”.The strategic strait in effect has been blocked by Tehran, leading to a rise in global oil prices.Meanwhile, Prime Minister Keir Starmer noted on Saturday that the UK would not use a base on Cyprus for Iran-related operations after a call with Cyprus President Nikos Christodoulides to discuss the base’s future.Chief of the Israeli military’s General Staff, Eyal Zamir, visits commanders and troops in Gaza [Handout/Israel’s army]How has Israel reacted to this?Israel’s military chief, Eyal Zamir, claimed that Iran used “a two-stage intercontinental ballistic missile with a range of 4,000km” to target the US-UK base in ⁠Diego Garcia.In a video statement, Zamir said: “These missiles were not intended to hit Israel. Their range reaches the capitals of Europe. Berlin, Paris and Rome are all within direct threat range.”Israel, a close US ally, has long said Iran’s missile and nuclear programmes pose a threat and has for decades lobbied the US to intervene militarily. But successive US administrations had resisted the pressure to launch military strikes on Iran. Instead, Washington imposed wide-ranging sanctions on Tehran to deter it from developing nuclear weapons.Washington and Tehran have not had diplomatic relations since shortly after Iranian students took over the US embassy in Iran in 1979 and held 66 Americans hostage in the wake of the Iranian Revolution that same year.In 2015, then-President Barack Obama signed a deal to limit Iran’s nuclear programme in return for sanctions relief. But the landmark agreement was opposed by Israel. Trump, who succeeded Obama, withdrew unilaterally from the nuclear deal and slapped sanctions back on Iran.In June, the US joined Israel in carrying out attacks on Iran during Israel’s 12-day war. The US hit key nuclear sites, and Trump claimed Iranian nuclear facilities were obliterated.Israeli Prime Minister Benjamin Netanyahu continued his war rhetoric against Iran, even as Tehran and Washington started talks over the nuclear issue late last year. Netanyahu had lambasted Obama for failing to include Tehran’s ballistic missile programme under the 2015 deal. Tehran has ruled out bringing the missile programme to the negotiating table.As the next round of talks was scheduled, the US and Israel attacked Iran three weeks ago, killing Supreme Leader Ali Khamenei. Oman, the mediator of the recent talks, said a deal had been “within reach”.Analysts said Netanyahu convinced Trump to start the war, which legal experts said appears to breach the UN Charter’s prohibition on aggression.They said Israel has been emboldened after its ongoing genocidal war in Gaza because it has not been held accountable for its war crimes. Israel’s military has killed more than 72,000 Palestinians and destroyed vast swaths of Gaza – home to more than two million Palestinians.