The furious FBI asked local cops to tell college student Luke Angel, 17, his drunken insult was "unacceptable". Luke yesterday admitted he fired off a single email criticising the US Government after seeing a TV programme about 9/11.

He said: "I don't remember exactly what I wrote as I was drunk. But I think I called Barack Obama a p***k. It was silly - the sort of thing you do when you're a teenager and have had a few."

Luke, of Silsoe, Beds, said it was "a bit extreme" for the FBI to act.

He added: "The police came and took my picture and told me I was banned from America forever. I don't really care but my parents aren't very happy."

A Beds Police spokesman said: "The individual sent an email to the White House full of abusive and threatening language. We were informed by the Metropolitan Police and went to see him. He said, 'Oh dear, it was me'."

Officers will take no criminal action.

Joanne Ferreira, of the US Department of Homeland Security, said there are about 60 reasons a person can be barred.

She added: "We are prohibited from discussing specific cases."