A new audio message purportedly from Osama Bin Laden should persuade the world to support the US-led war on terror, President George W Bush has said.
Some previous tapes have included video footage
"The Bin Laden tape should say to everybody the war on terror goes on, that there's still a danger to free nations," Mr Bush said.
In the tape, aired on the Arabic television station al-Jazeera, the speaker calls on the US to withdraw from Iraq and warns of more suicide attacks inside and outside the US.
It praises the continuing violence against US forces in Iraq, where more than 100 American troops have been killed since Mr Bush declared major hostilities over in May.
The recording emerged as Mr Bush was in Bangkok to attend the Asia Pacific Economic Cooperation (Apec) summit where anti-terrorism measures are high on the agenda.
"The appropriate authorities will analyse the tape," said White House spokesman Scott McClellan.
There have been a number of video and audio tapes said to be from Bin Laden or his aides handed to Arabic television stations since the US-led war in Afghanistan that followed 11 September 2001.
The last, aired on 28 September, was attributed to Bin Laden's deputy Ayman al-Zawahri and urged Muslims in Pakistan to overthrow President Pervez Musharraf.
The latest message, broadcast on Saturday, was in two parts.
In one, the voice called on young Muslims around the world, and "especially in the neighbouring countries and in Yemen" to go to Iraq to wage jihad or holy war.
"America has fallen into the quagmires of the Tigris and Euphrates. Bush thought that Iraq and its oil are easy spoils," the voice said.
"Now, he is in a critical situation."
The second tape was a message directed at the American people.
"I tell the American people: God willing, we will continue to fight you. We will continue the martyrdom operations inside and outside the United States until you end your injustice, abandon your stupidity," it said.
"We maintain our right to reply, at the appropriate time and place, to all the states that are taking part in this unjust war, particularly Britain, Spain, Australia, Poland, Japan, and Italy.
"The Islamic world's states that are taking part in this war, particularly the Gulf states, mainly Kuwait, the land base for the Crusader forces, will not be excluded from this."