A CIA spokesman said that the voice on the audiotape broadcast by an Arabic language TV channel is "likely" to be that of al Qaeda's No. 2 man, Ayman al-Zawahiri. The spokesman said that was not clear when it was recorded and added that the reference to Pakistani troops being in the tribal areas near the Afghan border could have been recorded any time in the past month or even longer. The tape calls on Pakistanis to overthrow President Pervez Musharraf -- a key ally of the United States in the war on terror.