A new audio message purportedly from Al-Qaida's second in command, Ayman al-Zawahiri, calls for Muslim unity and says U.S. policy in Iraq is headed for failure.
The new message, accompanied by a still picture of the al-Qaida deputy, was reported by the SITE Institute, a U.S. organization that monitors Web sites of Islamic militants. The contents of the tape have not been independently verified.
The institute says Zawahiri called President Bush's plan for Iraq a "gamble" headed to "the abyss."
Mr. Bush has ordered more than 20,000 additional U.S. troops to Iraq as part of a security operation aimed at ending sectarian violence.
The new al-Qaida message called on Muslims to unite and to go to Afghanistan, Iraq and other countries to wage Jihad (holy war).
It also says U.S. allies such as Egypt, Jordan and Saudi Arabia will reap what the speaker called a "bitter harvest."
Al-Qaida's leader Osama bin Laden has been absent from recent al-Qaida tapes. All of them have featured Zawahiri.
Earlier this year, the fugitive leader of Afghanistan's ousted Taleban regime, Mullah Mohammad Omar, said he had not seen bin Laden in five years.
U.S. officials have said they believe al-Qaida's leaders are hiding in the tribal areas along Pakistan's border with Afghanistan.
Some information for this report was provided by AP and Reuters.
