A suspect charged in the US for plotting the incident at RAF Fairford was stripped of his British citizenship last month after he fled to the Middle East, according to reports.
Mohammed Ali al-Hassani, a dual Iranian Iraqi national, is one of three men charged in the US with masterminding 18 Iran-backed terrorist plots in Europe.
US officials allege Al-Hassani “directed and paid associates in the United Kingdom to conduct preparatory steps and arrange logistics for the RAF Fairford” plot from Iran.
The Times has now reported that Al-Hassani was a UK citizen until his status was revoked last month.
The paper claims that the Home Secretary, Shabana Mahmood, had written to the suspect to say the decision had been taken because of national security concerns.
Al-Hassani left the UK weeks after the US went to war with Iran in February, it has been reported.
He and Iranian Mohsen Mohajeri are accused of using “a network of contacts in the United Kingdom” to orchestrate the Fairford plot.
Mohammad Baqer Saad Dawood al-Saadi, who was already in prison in the US, is accused of smuggling out coded messages to the pair from jail during phone calls to his family members.
The three men are accused of working for banned groups the Iranian Islamic Revolutionary Guard Corps (IRGC) and Iran-backed Iraqi militia Kataib Hezbollah, and were charged in an eight-count indictment which was unsealed in the US on Tuesday.
It is alleged they were behind 18 attacks in Europe, seven of which occurred in the UK – the most of any country – and attempting to bomb a synagogue in New York.
Last month, two men appeared at Westminster Magistrates’ Court charged under the National Security Act over the incident near the Gloucestershire air base on September 27 which saw three “suspicious” vans searched by police.
Mohmed Abdulkarim, 24, from London, is accused of assisting a foreign intelligence service by acting as an “intermediary” for an Iranian handler known only as Ali.
Nouman Essghir, 24, also from London, is accused of entering a prohibited place for a purpose prejudicial to the UK, relating to an alleged “reconnaissance” mission around a month before the Fairford incident.
According to the US Department of Justice (DOJ), Iraqi national Al-Hassani is accused of paying an unnamed individual to “perform pre-operational surveillance of RAF Fairford’s perimeter”.
It is also alleged he “tasked and paid several individuals to help him prepare for the plot, including by procuring vans and barrels of fuel, researching the purchase of chemical accelerants, including large quantities of potassium chloride, and purchasing metallic objects that could be used as explosive shrapnel”.
The DOJ said Al-Hassani instructed those individuals to outfit the vans “to create the appearance that they were used by a fuel delivery business and a swimming pool supply business”, and was “in frequent communication” with the drivers of the vans the morning of the incident.
The US removed its bombers from the base following the incident and Iran has denied any involvement.
A Home Office spokesperson said: “As there are ongoing legal proceedings, it would be inappropriate for us to comment.
“However, as we have said previously, it is no secret that we face a range of serious threats from Iran and this Government will continue to face them down – supporting our police and intelligence agencies with record funding and new powers to detect threats and keep us safe.”