Crowe picked up a best actor Oscar at the 2001 ceremony

The threat led to him being tailed by FBI agents during the filming of two of his movies.

Crowe told Australian GQ magazine that when told of the threat it "was the first conversation in my life that I'd ever heard the phrase al-Qaeda".

He added the FBI eventually thought the kidnap threat had been "overstated".

He was told the threat had been picked up by a French policewoman in Libya or Algeria in a recording.

'Sympathy plan'

The New Zealand-born, Australian-raised star said there was a "little touch of irony" to the plan.

He was told it was about "taking iconographic Americans out of the picture as sort of a cultural destabilisation plot", he said.

The actor said he initially thought it was all part of a publicity plan to gain sympathy from the Academy judges, but was eventually persuaded it was serious.

Crowe attended the 2001 Oscars, where he won best actor for Gladiator, surrounded by security agents.

"Suddenly it looks like I think I'm Elvis Presley, because everywhere I go there are all these FBI guys," he told the magazine.

As well as accompanying Crowe to the Oscars, agents also shadowed him while filming A Beautiful Mind and Master and Commander.