Diplomats said Wednesday they were closer to bringing about a cease-fire in the Gaza Strip, but fighting in the coastal territory persisted as the Palestinian death toll in the 19-day war passed 1,000.

Delegates from Hamas, meeting in Cairo with Egyptian mediators, said that the Islamist movement was willing to agree to a truce with Israel but that obstacles remained. Points of contention included whether a cease-fire would be temporary, when Israel would reopen checkpoints and who might patrol Gaza's border with Egypt to prevent smugglers from resupplying Hamas with weapons, officials involved in the talks said.

Details remained under wraps, but diplomats in the region said they were pushing for an immediate cease-fire, to be followed by further talks on border security and other issues.

Israel said it would send an emissary to Cairo on Thursday to hear details of a truce proposal that Egypt and Hamas have hammered out in recent days. Egyptian officials expressed optimism that a deal was near.

"We're working with Hamas, and we're working with the Israeli side," Hossam Zaki, an Egyptian Foreign Ministry official, told the BBC. "We hope to reach an outcome soon."

Israeli officials, however, were more cautious. They said Israel would not withdraw from Gaza unless Hamas first agreed to a long-term cease-fire. "Israel will not accept a situation where Hamas gets a temporary period of quiet just to rearm and regroup and that ends with further rocket barrages on Israel," Mark Regev, a spokesman for Israeli Prime Minister Ehud Olmert, told the Reuters news service.

Disagreements also persist within Israel's political leadership. Defense Minister Ehud Barak and Foreign Minister Tzipi Livni favor a quick end to the fighting, arguing that the war has dealt Hamas a severe setback and that there is little further to be gained, according to Israeli media reports. But Olmert, whose term ends next month, has resisted.

European diplomats said the framework for a truce was emerging but predicted that it could take days to win a final agreement. They said they were pressing for a deal to be struck before Tuesday, when Barack Obama is scheduled to be sworn in as president in Washington.

"My perception is we are very close to reaching a cease-fire," Spanish Foreign Minister Miguel Ángel Moratinos told reporters in the West Bank city of Ramallah after meeting with Palestinian Authority President Mahmoud Abbas. "They are very close, but still there is some work to be done."

While some Hamas delegates hinted at a breakthrough, others took a harder line. Salah al-Bardawil, a member of the Hamas negotiating team, said he doubted that Israel would be willing to withdraw its tanks and troops.

"What can we do? They are killing us and perpetuating massacres," he said at a brief news conference in Cairo. "You cannot blame someone who is being killed."

Bardawil said that Hamas negotiators had reached an understanding with Egyptian mediators but that it remained to be seen how Israel would respond. "There is no disagreement with the Egyptian leadership. The issue is differences over how to deal with the Zionist enemy," he said, referring to Israel.

Egypt is mediating the talks because Israel refuses to speak directly with Hamas, which it considers a terrorist organization.

In the meantime, Israeli forces and Hamas fighters continued to battle. Health officials in Gaza said more than 1,000 Palestinians have been killed and 4,700 injured since Israel began its offensive with airstrikes Dec. 27. A senior Israeli military official estimated Tuesday that a "few hundred" of the dead have been Hamas fighters.

Thirteen Israelis have died, including three civilians killed by Hamas rocket fire and 10 soldiers. Fighters in Gaza shot 14 more rockets into southern Israel on Wednesday, police said, but no injuries were reported.

The Israeli military said its warplanes and helicopters had struck more than 60 targets overnight, including smuggling tunnels, a police court in Gaza City and weapons caches. Military officials also said soldiers uncovered a stockpile of 20 rockets in a house in Gaza City.

Even as diplomats tried to reduce tensions Wednesday, some external forces threatened to make things worse.

More than a dozen Katyusha rockets landed in northern Israel, fired from Lebanon. No injuries or property damage were reported, but the fusillade was the second rocket attack on northern Israel in a week, raising fears that Lebanese fighters were trying to open a second front in the war.

No groups asserted responsibility for the strikes. The Israeli military said that it returned fire and that it viewed "the Lebanese government and military as responsible to prevent such attacks."

The Israeli military also confirmed that it had turned away an Iranian ship that was approaching Gaza. Iran is a key backer of Hamas. Iranian officials said the ship was loaded with humanitarian goods, which it would attempt to deliver to a nearby Egyptian port instead.

Also Wednesday, al-Qaeda leader Osama bin Laden interjected himself into the conflict. In a 22-minute audiotape posted on the Internet, bin Laden urged Muslims to attack Israel and vowed to open "new fronts" in al-Qaeda's fight against the United States.

Bin Laden also had harsh words for Arab leaders, saying they had failed to come to the aid of Gazans and accusing them of historically "avoiding their responsibility" to liberate Palestine. "If you are not persuaded to fight, then open the way to those who are persuaded," he said.

The audio file, which featured a still photo of bin Laden superimposed next to the al-Aqsa mosque in Jerusalem, was titled "A Call for Jihad to Stop the Aggression on Gaza." It was the first time bin Laden had been heard from publicly since May.

Al-Qaeda has almost no organizational presence in the Palestinian territories and considers Hamas a bitter ideological enemy. But the network has routinely tried to drum up support in the Muslim world by associating itself with Palestinian suffering.

Ayman al-Zawahiri, the network's deputy leader, released an audio recording Jan. 6 in which he blamed Obama for doing nothing to stop the Israeli invasion. Calling the war "Obama's gift to Israel," Zawahiri added: "He kills your brothers and sisters in Gaza mercilessly and without affection."

Bin Laden did not mention Obama by name in his speech but said the president-elect would receive a "heavy inheritance" from President Bush.

In an interview Wednesday with CBS News, Obama said his "number one" priority would be to weaken bin Laden and al-Qaeda so that they would no longer be capable of attacking the United States.

"My preference obviously would be to capture or kill him," Obama said. "But if we have so tightened the noose that he's in a cave somewhere and can't even communicate with his operatives, then we will meet our goal of protecting America."