The UN Security Council late Sunday deplored the mounting death toll in Gaza and appealed for an immediate ceasefire at an emergency session held on the worst day of fighting.
Meeting for two hours of urgent talks in New York, the 15-member Council also called for respect of international humanitarian law, including the protection of civilians.
"The members of the Security Council express serious concern about the growing numbers of casualties," said Rwandan Ambassador Eugene Richard Gasana, whose country chairs the 15-member council.
"The members of the Security Council call for an immediate cessation of hostilities based on the November 2012 ceasefire agreement" reached between Israel and Hamas, he added.
Palestinian president Mahmud Abbas had called for the emergency session, saying the "situation is intolerable" in Gaza and describing Israeli attacks as a "crime against humanity."
The 15-member Council met as UN Secretary-General Ban Ki-moon was holding talks with leaders in the region amid a spike in violence that killed more than 100 Palestinians in one day.
In their statement, the Council threw its support behind Egypt's bid to broker a truce and the high-profile peace mission by Ban, who is due in Kuwait on Monday before heading to Egypt, Israel and the Palestinian West Bank.
Palestinian representative to the United Nations Riyad Mansour welcomed the statement and said the appeal was a "test for Israel - if they are going to abide by all the elements and stop this aggression against our people."
"The hours and the minutes will reveal whether they will honor and respect this call by the Security Council," he said.
More than half of Sunday's Palestinian victims were killed in a blistering hours-long Israeli assault on Shejaiya, near Gaza City, which began before dawn and has claimed more than 100 Palestinian lives.
At the outset of the meeting, the Palestinian representative described the assault on Shejaiya as a "heinous massacre" and urged the Security Council to take a decisive stand.
Israel seeking 'quiet'
Israeli Ambassador Ron Prosor shot back, saying that Israel had thrice agreed to ceasefire offers from Egypt and was acting in self-defense from rocket attacks launched by Palestinian Hamas militants.
"The equation is simple. It's going to be quiet in Israel when it's going to be quiet to Gaza. We are trying to defend the people of Israel," he said.
The Council's 15 members held a meeting on Gaza Friday but failed to reach agreement on a joint declaration.
Since the conflict began on July 8, the Council also held a first inconclusive meeting on July 10 before calling for a ceasefire in a unanimous declaration.
Ban, whose envoy negotiated a brief humanitarian truce last week, condemned the "atrocious action" in Shejaiya and urged Israel to "exercise maximum restraint."
"Too many innocent people are dying... (and) living in constant fear," Ban told a news conference in Doha.
So far, truce efforts have been rejected by Hamas which has pressed on with its own attacks, undaunted by the Israeli bombardment by land, sea and air.
In the early hours of Monday Israeli jets carried out strikes throughout Gaza, including in southern Rafah and Khan Yunis and northern Beit Lahiya. Israel began ground operations in Gaza on Thursday.