LONDON — Britain formally accused Iran's Islamic Revolutionary Guard Corps of coordinating a foiled terror plot against RAF Fairford, the Gloucestershire airbase that hosts U.S. B-1 and B-52 bombers, escalating a confrontation that's already drawn fresh sanctions and a summoned ambassador.

Prime Minister Andy Burnham told Parliament Monday the September plot was "highly likely to have been coordinated in Iran, almost certainly directed by Iran's Islamic Revolutionary Guard," declaring, "We will not tolerate these threats on our soil." Home Secretary Shabana Mahmood said a known individual based in Iran is believed to have coordinated the operation, though UK officials did not name that person publicly.

The plot traces back to September 27, when seven British men — most in their 20s, including one British-Iranian national — were arrested near the base after reports of suspicious vehicles. Police recovered petrol in seized vans but no viable explosives, and all seven were released on bail without charge. In the plot's aftermath, the U.S. reportedly withdrew roughly a dozen B-1 bombers from Fairford, with unnamed officials citing concerns about a possible small-drone attack.

Sanctions and denial

Foreign Secretary Ed Miliband summoned Iran's ambassador, Seyed Ali Mousavi, and the UK imposed sanctions — asset freezes and travel bans — on two Iranian nationals: Ruhollah Bazghandi, described by British officials as an IRGC counterespionage chief, and Shahram Ali Reza Tamarzadeh Jakki, identified as a facilitator for the so-called Zindashti criminal network. Neither man was explicitly named as having organized the Fairford incident itself.

"TEHRAN HAS HAD NO INVOLVEMENT IN THIS MATTER."

Iran rejected the accusation outright. Ambassador Mousavi said, via Iran's state IRNA news agency, that "Tehran has had no involvement in this matter," challenging Britain to produce evidence. Iran's Foreign Ministry went further Monday, calling the UK's claims an "ugly plot" designed to "evade accountability" and a "clumsy false flag operation."

The confrontation lands weeks after Britain formally designated the IRGC a terrorist organization in July, and days after roughly 30 countries — including the U.S., Canada, France and Germany — jointly condemned what they called Iran's pattern of "violent attacks, including... lethal plotting, arson, sabotage, cyber-attacks." With bombers temporarily relocated and both governments trading public accusations, diplomats on both sides say the standoff shows little sign of cooling in the near term.