"Whatever Baitullah Mehsud and his associates are doing in the name of Islam is not a jihad, and in fact it is rioting and terrorism," Zainuddin told the AP after a mosque suicide bombing attack, blamed on Mehsud, killed 33 people. "Islam stands for peace, not for terrorism."

Zainuddin's motive for criticizing Mehsud was not clear, but there was speculation that he was trying to portray himself as a more moderate alternative to the Taliban leader, although there appeared to be little or no differences between the two over fighting U.S. and NATO forces in Afghanistan.

Daily bombing runs and artillery barrages have been softening up militant targets in South Waziristan for about a week and ground troops have moved into position, the military says, though it says the main offensive has not yet started.