United Nation Secretary-General Antonio Guterres told the UN Security Council on Sunday that hostilities in Israel and Gaza were "utterly appalling" and called for an immediate end to fighting.
Opening the 15-member council's first public meeting on the conflict, Guterres said the UN was "actively engaging all sides toward an immediate ceasefire" and called on them "to allow mediation efforts to intensify and succeed."
The death toll in Gaza jumped to 181 overnight, including 47 children, amid an intensive IDF air and artillery barrage since the fighting erupted last Monday.
Ten people have been killed in Israel, including two children, in thousands of rocket attacks by Hamas and other terror groups.
Israel says its Iron Dome missile defense system has intercepted 90% of the rockets headed for inhabited areas and that many of the projectiles have struck inside Gaza itself, causing injury and death.
"Each time Israel hears a foreign leader speak of its right to defend itself it is further emboldened to continue murdering entire families in their sleep," Palestinian Foreign Minister Riyad al-Malki told the Security Council.
Israel's UN Ambassador Gilad Erdan said Israel's response to indiscriminate attacks by Hamas strictly adhered to international law and that the country was taking "unparalleled steps to prevent civilian casualties."
"Israel uses its missiles to protect its children. Hamas uses children to protect its missiles," Erdan said.
The Security Council met privately twice last week over the worsening violence, but has so far been unable to agree on a public statement because the United States - a strong ally of Israel - did not believe it would be helpful, diplomats said.
"We call upon the U.S. to shoulder its responsibilities, take a just position, and together with most of the international community support the Security Council in easing the situation," said Chinese Foreign Minister Wang Yi, who chaired Sunday's meeting as China is council president for May.
UN Middle East envoy Tor Wennesland urged the international community to "take action now to enable the parties to step back from the brink."
Truce efforts by Egypt, Qatar and the United Nations have so far offered no sign of progress.
The United States sent an envoy to the region and President Joe Biden spoke with Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas on Saturday.
"Concessions must be made as a price to be paid for peace so as to spare people from paying the heavy price of war," Egyptian Foreign Minister Sameh Shoukry told the Security Council.
A source in Jerusalem said earlier Sunday that an imminent ceasefire had not been on the agenda of a four-hour security cabinet meeting.
He said that ministers had approved the continuation of the IDF assault on terror targets in Gaza, dubbed Operation Guardian of the Walls.
A source in the cabinet also said the operation would end this week but added that, "There is no great international pressure to stop."