ERBIL, Kurdistan Region of Iraq – Iran on Tuesday summoned the British ambassador to Iran over London’s accusations of a link between Tehran and a foiled alleged plot targeting the RAF Fairford airbase in late September, demanding evidence to support the claims and warning that it would “reconsider bilateral relations.”

On Monday, UK Prime Minister Andy Burnham said that a suspected attack  planned on the base was “highly likely” to have been coordinated in Iran and “almost certainly” directed by the Islamic Revolutionary Guard Corps (IRGC), with London imposing sanctions on two Iranian nationals in response.

The UK will not tolerate “these threats on our soil,” he said, adding that “we will crack down on Iran's use of criminal networks, using our full range of powers to target them and their funding streams.”

“The British government must immediately provide evidence and documentation supporting its allegations regarding the purported incident at Fairford base; otherwise, the Islamic Republic of Iran will seriously reconsider bilateral relations,” read a statement from Iran’s foreign ministry.

London will bear “responsibility for the consequences,” it said during the summoning of the British Ambassador to Iran, Hugo Shorter, and conveying Tehran’s strong condemnation of London’s “irresponsible and destructive approach.”

It also described the British stance “as part of an anti-Iran campaign.”

On 27 September, suspicious activity involving three vehicles near the US-linked base in England's Gloucestershire prompted a major counter-terrorism probe and the evacuation of the surrounding neighborhood.

Six London-based British citizens were arrested in the September incident, including a UK-Iranian dual national; all men in their mid-20s were released on bail, drawing rebuke from Washington.

Earlier in December, the US confirmed that it had withdrawn all B-1 bombers from the British airbase RAF Fairford, following the September incident.

On Monday, UK Foreign Secretary Ed Miliband announced additional sanctions against two Iranian nationals, according to a government statement.

The two Iranian nationals were sanctioned for their alleged role in “facilitating or engaging in hostile activity on behalf of the Iranian regime, with the clear intent of threatening, planning, or conducting attacks overseas,” the statement said.

When asked about Iran’s alleged involvement in the September incident, US President Donald Trump said earlier in October, “I wouldn’t have done that,” while Secretary of State Marco Rubio alleged that a “foreign actor” was involved.