"First, is this his beard?'' Republican Senator Norm Coleman asked the spy chief.

"Do we expect that - is it a signal?''

Questions over the elusive Saudi extremist's beard cropped up at a ccongressional hearing overnight featuring top US security experts, including Director of National Intelligence Michael McConnell.

"First, is this his beard?'' Republican Senator Norm Coleman asked the spy chief.

"Do we expect that - is it a signal?''

Mr McConnell swiftly rejected any possibility that the hair in bin Laden's chin was intended to send any signal to his al-Qaeda members.

"So far, we do not think there's been a signal. He's done this periodically, as has (Ayman al-) Zawahiri (the group's second-in-command), and there has not been a correlation necessarily between one of these tapes or a public statement and a particular event,'' Mr McConnell said.

But he wondered whether bin Laden's beard was genuine.

"The big question in the community this morning, 'Is that beard real,' because as you know, just a few years ago, the last time he appeared, it was very different,'' he said.

"So we don't know if it's dyed and trimmed or real, but that's one of the things we're looking at. But no specific message.''