ISLAMABAD - Pakistan's President Asif Ali Zardari said on Monday that the whereabouts of al Qaeda leader Osama bin Laden remained a mystery and there was a suspicion that he could be dead.

Speaking to international media, Zardari said U.S. officials had told him that they had no trace of the al Qaeda chief, although they habitually say he is most likely in Pakistan.

Pakistan's own intelligence agencies were no wiser, either, Zardari said.

There is no news, the president said. They obviously feel that he does not exist anymore but that's not confirmed, we can't confirm that.

Al Jazeera aired excerpts of an audio recording in March in which the speaker's voice sounded like earlier messages from bin Laden, who has eluded all efforts to catch him since al Qaeda carried out the September 11, 2001 attacks on the United States.

Bin Laden, if he is still alive, turned 52 on March 10, but he is known to suffer from ill-health.

There have been reports that he had died of natural causes in the past, but they have never been corroborated, and security analysts believe intelligence agencies monitoring jihadi websites on the Internet would have picked up some chatter.

Pakistan