Palestinian President Mahmoud Abbas on Sunday called on his rivals in Hamas to renew a truce with Israel to avoid further bloodshed in Gaza.

The Israeli military assault began Saturday, a little over a week after a six-month truce expired and militants began bombarding southern Israel with rockets. The assault has killed more than 270 Palestinians, most of them militants.

After meeting with Egyptian President Hosni Mubarak in Cairo, the moderate Palestinian president appealed to leaders in the militant Hamas group "to stop the bloodshed."

"We have warned of this grave danger and said that we should remove all the pretexts used by Israel," said Abbas. "We all hope to end the aggression and return to the calm. We want to protect Gaza."

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Hamas rules Gaza, the coastal territory it seized control of in street battles with Abbas' Fatah movement in June 2007. Abbas and his government control the West Bank.

Egyptian Foreign Minister Ahmed Aboul Gheit said a renewal of the truce should be a priority.

"There has been a calm and we should work to restore it," said Aboul Gheit.

Hamas leaders have refused to extend the truce. Hamas' prime minister, Ismail Haniyeh, declared his movement would not be cowed.

In Damascus, Syria, Hamas' top leader, Khaled Mashaal, called on Palestinians to rekindle their fight against Israel. "This is the time for a third uprising," he said on Saturday.

Egypt is under attack by many in the Arab world for its role, along with Israel, in closing the Gaza Strip after the militant Hamas took control there. Egypt's closure of Gaza's southern crossing point is seen by some as abetting Israel's siege of the crowded strip of land, home to 1.5 million people.

Aboul Gheit said a truce extension would lead to the opening of the Gaza crossings.

In a meeting Wednesday in Cairo, Arab foreign ministers will discuss a pan-Arab response to the Israeli offensive, including deciding on a Qatari and Syrian proposal to convene an emergency Arab summit this weekend.

Israeli Prime Minister Ehud Olmert said Sunday the offensive against Gaza militants is "liable to take longer than we can foresee at this moment."

Olmert said the operation is intended to restore tranquility to Israel's south, where lives have been disrupted by militant rocket and mortar attacks.

It was not immediately clear how many civilians were killed, but Palestinian officials say the majority of the dead have been militants.

Egypt has said that it was ready to receive all Gazans wounded in the attacks for treatment at its hospitals, but so far none of the injured have been taken across the border.