Some previous tapes have included video footage
A message attributed to Osama Bin Laden has called on the US to withdraw from Iraq and warned of more suicide attacks in and outside the US.
The audio tape message, broadcast by the Arabic television station al-Jazeera, praises the continuing violence against US forces in Iraq.
The attacks have claimed the lives of more than 100 soldiers since the end of major hostilities in May.
White House spokesman Scott McClellan said the tape was a reminder that the global war on terrorism continued and "that's why we are taking the fight to the killers".
"The appropriate authorities will analyse the tape," he said.
The US blames Osama Bin Laden's al-Qaeda network for the 11 September attacks that prompted President George W Bush to launch his "war on terror".
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 US-appointed Governing Council in Iraq on Saturday issued a statement warning of growing violence and instability in the country.
The statement appeals to Iraqis to abstain from acts of violence, saying no-one is above the law and those who violate it will be punished.
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."
The last tape attributed to Bin Laden himself was aired on 10 September this year just as Americans prepared to mark the second anniversary of the attacks on New York and Washington.
CIA experts said the voice on that tape "probably was Bin Laden" but analysts could not determine when the video footage featuring Bin Laden and his aide Ayman al-Zawahri which accompanied the separate audio recordings were made.