Britain's leader is Andy Burnham.

He spoke on Monday.

He said there was a plan to attack a U.S. air base in England.

He said Iran's Revolutionary Guard "almost certainly" led the plan.

He told lawmakers the plan was likely made in Iran.

He said Britain will not accept these threats.

The base is RAF Fairford.

American bombers use it to strike Iran in the war.

Police arrested seven men.

They are all in their 20s.

All of them are out on bail.

No one has been charged.

Six are British.

One has two passports: U.K. and Iran.

On Sept. 27, many people near the base left their homes.

Armed police and army bomb experts went to the area.

Police later said they found gasoline in three vans.

The vans link to the first five suspects.

They found no explosives.

Iran says it was not involved.

But Iran says any base used to attack it is a fair target.

Britain called the Iranian ambassador on Monday.

He said again that Tehran was not involved.

He asked the U.K. to give evidence.

Britain also put two Iranians on its sanctions list.

One is the head of secret operations for the Revolutionary Guard.

The Pentagon said the U.S. moved its bombers from RAF Fairford last week.

They went back to their home bases.