"I expect the Jihadi influence to spread after the Americans' exit from Iraq, and to move towards Jerusalem," Ayman Al-Zawahri said in response to questions compiled by Islamist Web sites.
"We promise our Muslim brothers that we will do our utmost to strike Jews in Israel and abroad with help and guidance from God," he said to those asking when attacks on Israel would take place.
Last week, the Al-Qaida leader called on Muslims to strike Israeli, Jewish and American interests in revenge for Israel's ground incursion in the Gaza Strip in early March.
Al-Zawahri on Wednesday also said that Osama bin Laden was well and reports he was sick were false.
"Sheikh Osama bin Laden is in good health," the militant leader said. "The ill-intentioned always try to circulate false reports about him being sick."
The audio message, which was accompanied by a 46-page English transcript, was the first installment of answers to a raft of online questions and focused mainly on future al-Qaida efforts elsewhere in the region, particularly Egypt.
Al-Zawahri, who, like Bin Laden is believed to be hiding in Afghanistan or Pakistan, also denounced the United Nations.
"The United Nations is an enemy of Islam and Muslims," he said. He defended attacks on UN offices in an apparent reference to twin bomb attacks on UN buildings in Algiers which killed 41 people in December and the 2003 bombing of a UN building in Baghdad which killed 22.
In response to criticism Wednesday about the organization's notoriously brutal tactics, Al-Zawahri maintained that Al-Qaida does not kill innocents.
"We haven't killed the innocents, not in Baghdad nor in Morocco, nor in Algeria, nor anywhere else," he said according to the English transcript which, like the audio message, appeared on Web sites linked to the group.
He also predicted the end of the Saudi state, which is swimming against the tide of history and the government of his native Egypt, which he called "a corrupt, rotten regime [that] cannot possibly continue."
Many of the questions he chose to answer focused on restarting the jihad in Egypt, which Zawahri himself helped begin and was crushed by the government in the 1990s.
"The days will reveal to you what you didn't know, and news will come to you from those who didn't have it," he said quoting an old Arabic proverb, about when the jihad would begin again in Egypt, and counseled patience.
Egypt's plainclothes State Security officers and uniformed police were declared permissible to kill in the struggle for Egypt and he hinted that he had supporters in the Egyptian army, like the man who assassinated former Egyptian President Anwar Sadat in 1981.
"The Egyptian army which produced Khalid al-Islambouli ... continues to be full of those whose hearts boil with jealousy for Islam and Muslims and who long for the opportunity to remove the corrupt gang which rules Egypt," he said.
Though the tape could not be independently verified, the message bore the logo of Al-Qaida's media arm, al-Sahab, and appeared on Web sites linked to the organization.