Al Qaeda's deputy leader Ayman al-Zawahri said offences against Prophet Mohammad were part of a "crusader" campaign led by the United States, and he urged Muslims to conduct new strikes on the West.

In a video broadcast Saturday on Al-Jazeera Arab satellite network, Al Qaeda's No. 2 leader criticized the West for insulting Islam's prophet.

Referring to cartoons of the prophet that have been printed in European newspapers, Zawahri said: "They did it on purpose and they continue to do it without apologizing, even though no one dares to harm Jews or to challenge Jewish claims about the Holocaust, nor even to insult homosexuals."

Zawahri, wearing a black turban -- a symbol of war to Muslims -- and seated in front of a curtained window, waived his right hand while speaking, emphasizing his message.

"The insults against Prophet Muhammad are not the result of freedom of opinion but because what is sacred has changed in this culture,'' he said.

"The Prophet Mohammed, prayers be upon him, and Jesus Christ, peace be upon him, are not sacred anymore, while Semites and the Holocaust and homosexuality have become sacred.''

Zawahri added: "(Muslims have to) inflict losses on the crusader West, especially to its economic infrastructure, with strikes that would make it bleed for years."

"The strikes on New York, Washington, Madrid and London are the best examples," he said.

He also called on Muslims to boycott countries that published the satirical cartoons, including Denmark, Norway, France and Germany, and said Muslims should prevent the West from "stealing Muslims' oil.

"We have to prevent the crusader West from stealing the Muslims' oil which is being drained in the biggest robbery in history," he said.

Saturday's tape came as U.S. President George W. Bush wrapped up a visit to Pakistan. Zawahri and Bin Laden are believed to be hiding in the Afghanistan-Pakistan border region.

Zawahri described Bush as a "butcher" in a tape aired by the Qatar-based Al Jazeera satellite channel in January, and said a recent U.S. air strike in Pakistan targeting him had killed only innocent people.