Al Qaeda leader Osama bin Laden called on Muslims to rise in a jihad (holy struggle) against the Israeli offensive in Gaza and accused Arab leaders of collusion with Israel, in an audio tape issued on Wednesday.
The Saudi-born militant also said outgoing U.S. President George W. Bush had left his successor, President-elect Barack Obama, a sapping legacy of war and economic woe, Reuters reported.
Bin Laden said the global financial crisis had exposed the waning U.S. influence in world affairs and would in turn weaken its ally Israel.
"Our brothers in Palestine, you have suffered a lot.... the Muslims sympathize with you in what they see and hear. We, the mujahideen, sympathize with you also..." bin Laden said on the tape entitled 'A Call for Jihad to Stop the Aggression against Gaza', that appeared on Islamist websites.
"We are with you and we will not let you down. Our fate is tied to yours in fighting the Crusader-Zionist (Western-Israeli) coalition, in fighting until victory or martyrdom."
He called on Muslims to rise in support of Gazans and not to rely on Arab leaders "the great majority of whom are allied with the Crusader-Zionist coalition."
The Palestinian death toll from a 19-day-old Israeli offensive against the Islamist Hamas movement in Gaza has passed 1,000. Israel says it has lost three civilians, hit by rockets or mortars from Gaza, and 10 soldiers.
In Washington, the White House said the tape, in which bin Laden also appealed to Muslims to donate money to militants in a "financial jihad," showed his isolation.
"It appears this tape demonstrates his isolation and continued attempts to remain relevant at a time when al Qaeda's ideology, mission and agenda are being questioned and challenged throughout the world," White House spokesman Gordon Johndroe said.
"This also looks to be an effort to raise money as part of their ongoing propaganda campaign," he said.
In the 22-minute tape, bin Laden said the United States was losing its dominant world position and that this was due to al Qaeda's campaign. He said Bush was leaving a burden of war and crisis for Obama.
"Seventy-five percent of the American people are glad about the departure of a president who got them bogged down in wars they have nothing to do with and drowned them in economic turmoil up their ears."
"And he left a heavy inheritance for his successor ... the legacy of long guerrilla war with a patient and stubborn foe. If he pulls out of the war, it is military defeat and if he continues he drowns in economic crisis," bin Laden said
"The jihad of your sons against the Crusader-Zionist coalition is one of the key reasons for these destructive effects among our enemies," bin Laden told Muslims. "God has bestowed us with the patience to continue the path of jihad for another seven years, and seven and seven... The question is, can America continue its war with us for several more decades to come? Reports and evidence would suggest otherwise."
The FBI said the message does not represent a threat to Obama's when he assumes the presidency on January 20.
"We have no specific or credible threat for the inauguration," FBI spokesman Richard Kolko said.
Bin Laden's last message was in May 2008 when he also focused on Gaza, calling on Muslims to try to help end the blockade of the area.
He has placed growing emphasis on the Israeli-Palestinian conflict in recent years and Wednesday's audio tape was accompanied by a still picture of bin Laden and an image of al-Aqsa mosque in Jerusalem, Islam's third holiest shrine.
Al Qaeda, the network behind the September 11, 2001 attacks on U.S. cities, has regularly called for attacks on Israel.
It was widely blamed for a 2002 suicide attack on an Israeli-owned hotel in Kenya and a simultaneous failed attempt to shoot down an Israeli charter jet near Mombasa airport.