"God has bestowed us with the patience to continue the path of jihad for another seven years, and seven and seven years," bin Laden said on the tape dated in the current Islamic month. "The question is, can America continue its war with us for several more decades to come? Reports and evidence would suggest otherwise."
Bin Laden last appeared in an audio tape in May and also focused on Gaza, calling on Muslims to try to help to end the blockade of the area. The al-Qaeda leader has placed growing emphasis on the Israeli-Palestinian conflict in recent years.
The conflict that incited Mr. bin Laden's message deepened and widened on Wednesday as Israeli forces prepared to storm Gaza City while also firing rockets into Lebanon in response to an earlier attack.
England’s Guardian newspaper reports that Israeli troops reached the outskirts of Gaza City.
There was heavy fighting in northern Gaza and around the edges of Gaza City, from where Israeli troops have mounted raids to within a mile of the city centre....
Israel's military said it hit 60 sites overnight, including the police headquarters in Gaza City that had been hit on the first day of the operation, as well as rocket launching sites, weapons stores and 35 smuggling tunnels under the border with Egypt. Six Israeli soldiers were injured.
Analysts say Israel may be holding back from all-out urban warfare in Gaza City.
Intense street fighting could complicate truce efforts and cause heavy casualties on both sides, which they say would be a politically risky move less than a month before Israel's parliamentary election.
Israel began its offensive Dec. 27 in retaliation for rockets fired into Israel by Palestinian militants in Gaza. Since the fighting began, a series of new fronts seems to have opened up. The Associated Press reports that Israeli troops have shelled south Lebanon.
Israeli forces fired artillery north into Lebanon on Wednesday in response to a rocket attack, and Lebanese troops dismantled more rockets that were set to be fired, Lebanese security officials said.
The exchange was the second since Israel launched an offensive in Gaza against Hamas on its southern flank on Dec. 27 and threatens to ignite a new front in the north.
Israeli forces fear the attack was instigated by the military wing of Hezbollah, a political organization in Lebanon. But Hezbollah has denied any involvement in the attack, according to Haaretz, an English-language daily in Tel Aviv.
Israeli officials have expressed concern that militants in Lebanon could try to open a second front in the Gaza campaign in solidarity with Hamas.
A Hezbollah minister in Lebanon's Cabinet denied any involvement by the militant group in the firing of the rockets on Thursday. In 2006, Hezbollah guerrillas in Lebanon fired almost 4000 rockets at Israel during the Second Lebanon War.
A further 4,350 people have been wounded, according to the Palestinian emergency services.
On the Israeli side, 10 soldiers and three civilians have been killed in combat or by rocket attacks since the Jewish state began its offensive.
As fighting mounts, Israel's government is divided over how to proceed, reports Haaretz.
Defense Minister Ehud Barak is promoting a week-long "humanitarian cease-fire" in the Gaza Strip. In contrast, Prime Minister Ehud Olmert believes the military operation still has not achieved its goals.
Olmert is delaying a meeting with senior ministers in an effort to allow the military operations in Gaza to continue.
On Tuesday, Olmert did not meet with his "troika" - Barak and Foreign Minister Tzipi Livni, both of whom support a cease-fire. On Wednesday, he will not convene the political-security cabinet to discuss whether the operations should go on.
International criticism has mounted, according to Agence France-Presse.
The offensive -- Israel's deadliest ever against Gaza -- has sparked withering criticism and protests and concern about a humanitarian crisis breaking out in the densely populated territory where half of the population is under 18 years of age.
Mr Ban said he plans to step up diplomatic efforts to get both sides to adhere to a UN cease-fire resolution calling for an end to Israel's air and ground offensive in Gaza and Hamas' rocketing of southern Israel.
"To both sides, I say: Just stop, now," he said. "Too many people have died. There has been too much civilian suffering. Too many people, Israelis and Palestinians, live in daily fear of their lives."