Egypt ? Al-Qaida’s No. 2 Ayman al-Zawahri warned of “traitors” among insurgents in Iraq and called on Iraqi Sunni Arab tribes to purge those who help the Americans in a new videotape posted today on the Web.

Al-Zawahri’s comments were aimed at undermining so-called “awakening councils” – groups of Sunni tribesmen that the U.S. military has backed to help fight al-Qaida in Iraq and its allies.

Some Sunni insurgent groups have fought alongside American forces, and the U.S. military has touted the councils as a major factor in reducing violence in war-torn regions like Iraq’s Anbar province.

The mujahedeen “must throw out the bribe-taking collaborators from among their ranks, those who sold out their faith and fight under the banner of the cross. They must expose them to the Muslim world,” al-Zawahri said. “Those who support the Americans are despicable scum,” he said, calling on the “noble tribes of Iraq, those that defend Islam, to stand up to this scum.”