The Al-Jazeera satellite television station aired the message throughout the Arab world Tuesday. U.S. counter-terrorism officials in Washington said the audio tape was probably a real recording of bin Laden, and that a technical analysis was planned to authenticate it.
Since U.S. forces apparently had bin Laden cornered in the Afghanistan's Tora Bora mountain range in late 2001, his whereabouts have been unknown.
On Wednesday, the commander of U.S. forces in Afghanistan said the taped threats would not affect efforts to track down al Qaeda remnants there.
Lt. Gen. Dan McNeill also said he saw no reason to change security at Bagram Air Base, the headquarters for troops in Afghanistan.
"This to me is still not compelling evidence that he's alive nor is it compelling evidence that he's dead," McNeill said.
"We are winning this thing and we are going to win it and whatever he might want to utter on tape causes me no great concern," McNeill said.
Secretary of State Colin Powell said the comments, broadcast on the first day of the major Islamic holiday Eid al-Adha, bolstered U.S. allegations that Iraq is harboring al Qaeda operatives.
"This nexus between terrorists and states that are developing weapons of mass destruction can no longer be looked away from and ignored," Powell told the Senate Budget Committee.
In remarks to the U.N. Security Council last Wednesday, Powell accused Iraq of harboring al Qaeda fugitive Abu Musaab Zarqawi, who has been linked to the murder of a U.S. diplomat in Jordan and poison plots in a half-dozen European countries.
But some Middle East experts have questioned ties between bin Laden's Islamic extremists and Saddam's government, which nominally adheres to a Pan-Arabic socialistic doctrine called Baathism.
In the tape, the speaker said Iraq was governed by socialist "infidels," including Saddam. But he said that it was acceptable for Muslims to fight on behalf of Iraqi "socialists" because "in these circumstances" their interests "intersect in fighting against the Crusaders," or Christians.
The Iraqi government has repeatedly denied links to al Qaeda. The tape has not been reported on Iraqi media and most Iraqis do not have satellite dishes.
In an interview Wednesday with the Lebanese Broadcasting Corp., Iraqi Vice President Taha Yassin Ramadan denied his country has any links with al Qaeda or has sheltered any members of bin Laden's group. He claimed the United States was using the al Qaeda allegation as a pretext for war.
"They are looking for oil, for Arab oil and want to protect the Zionist entity that usurped the land of the Arabs," Ramadan said.
On the tape, the speaker urged Iraqis to profit from the lessons learned by al Qaeda fighters in the war against the Americans and their allies in Afghanistan.
He said the strategy of digging camouflaged trenches was especially effective against U.S. bombing in Tora Bora.
"We advise about the importance of drawing the enemy into long, close and exhausting fighting, taking advantage of camouflaged positions in plains, farms, mountains and cities," he said.
The speaker urged the Iraqis to draw the Americans into urban combat, saying "the thing that the enemy fears the most is to fight a city war" because the United States is afraid of suffering "big casualties."
U.S. military planners fear Saddam might ring Baghdad with his best troops of the elite Republican Guard and draw U.S. forces into bloody street fighting where they could not use their high-tech weapons for fear of causing massive civilian casualties.