Osama bin Laden issued ominous new threats in an audiotape broadcast Sunday, purportedly saying the West was at war with Islam and calling on his followers to go to Sudan to fight a proposed UN force.

This is an undated file photo of Osama bin Laden. The terror suspect purportedly said in an audio tape broadcast by Al-Jazeera television that the West's decision to cut off funds to the Palestinians proved that the United States and Europe were at war with Islam. [AP]

In his first new message in three months, bin Laden said the West's decision to cut off funds to the Palestinians because their Hamas leaders refuse to recognize Israel proved that the United States and Europe were conducting "a Zionist crusader war on Islam."

"The blockade which the West is imposing on the government of Hamas proves that there is a Zionist crusader war on Islam," said the speaker on the tape broadcast by the Al-Jazeera network.

"I say that this war is the joint responsibility of the people and the governments. While the war continues, the people renew their allegiance to their rulers and politicians and continue to send their sons to our countries to fight us."

The authenticity of the tape could not immediately be verified.

Bin Laden also addressed the conflict in Sudan, where he was based before being expelled under threats from the United States. He then moved to Afghanistan and is believed to be hiding out in the rugged mountains on the Pakistani side of their common border.

A three-year conflict between Darfur's rebels and the Arab-dominated central government has caused about 180,000 deaths ¡ª most from disease and hunger ¡ª and displaced 2 million people.

The United Nations has described the conflict as the world's gravest humanitarian crisis. The United States has described it as genocide.

Negotiators are trying to broker a peace deal between warring factions by an April 30 deadline. Members of the African Union have agreed in principle to hand over peacekeeping duties to the United Nations beginning Sept. 30.

"I call on mujahedeen and their supporters, especially in Sudan and the Arab peninsula, to prepare for long war again the crusader plunderers in Western Sudan. Our goal is not defending the Khartoum government but to defend Islam, its land and its people," bin Laden purportedly said.

It was the first purported new message from bin Laden since Jan. 19. In that audiotape, he warned that his fighters were preparing new attacks in the United States but offered the American people a "long-term truce" without specifying the conditions.

That tape was posted in full on a Web site a month later and included a vow by the terrorist chieftain never to be captured alive.