In the message, purportedly from Ayman al-Zawahiri, the speaker criticised Obama's foreign policy positions on Afghanistan and Israel and ridiculed the president-elect's world view, comparing him unfavourably to Malcolm X, the fiery African-American Muslim activist from the 1950s and 1960s.

The posting, an 11 minute and 23 second audio message in Arabic with subtitles in English, appeared on the Web yesterday. Its authenticity could not be confirmed.

It shows a graphic with the words "The departure of Bush and the arrival of Obama." That graphic also contains a still image of Malcolm X on a Muslim prayer rug in a mosque; images of Obama, wearing a Jewish skullcap, at the Western Wall in Jerusalem, and a picture of al-Zawahiri.

There are also archival videos in the message, including clips of speeches from Malcolm X.

"You have reached the position of president, and a heavy legacy of failure and crimes awaits you. A failure in Iraq to which you have admitted, and a failure in Afghanistan to which the commanders of your army have admitted," the message said.

The speaker also said Obama's plan to pull troops from Iraq and send them to Afghanistan "is a policy which was destined for failure before it was born".

"If you still want to be stubborn about America's failure in Afghanistan, then remember the fate of (George E.) Bush and Pervez Musharraf, and the fate of the Soviets and British before them," the message said.

Delicious flesh

"And be aware that the dogs of Afghanistan have found the flesh of your soldiers to be delicious, so send thousands after thousands to them."

It said Obama appeared "to be captive to the same criminal American mentality towards the world and towards the Muslims". The speaker cited Muslims' ire toward Obama's support of Israel.

The message said Obama represented the "direct opposite of honourable black Americans" like Malcolm X.

The speaker also said Obama, former and current secretaries of state Colin Powell and Condoleezza Rice, and "your likes" fit Malcolm X's description of "house slaves".

The English translation of the message used the term "House Negroes", Malcolm X's term for blacks who were subservient to Whites. (CNN.com)