The world implored Israel and Hamas Saturday to end hostilities as warplanes pounded Gaza for a fifth straight day, killing at least 30 Palestinians, and militants replied with rockets.
Both sides have brushed off calls for a truce, and Israel is building up troops and armour on the Gaza border for a possible ground invasion.
As the Palestinian death toll hit 135, and with no Israelis killed, the UN Security Council unanimously urged Israel and Hamas to respect "international humanitarian laws" and stop the loss of life.
The 15-member council urged a return to the "calm and restitution of the November 2012 ceasefire", referring to Gaza's last deadly full-scale conflict.
Israel's aerial campaign -- the largest and deadliest since 2012 -- saw strikes start early on Saturday, including one that hit a centre for the handicapped, and another that killed two nephews of Gaza's former Hamas premier, Ismail Haniya.
Rockets fired from Gaza targeted Jerusalem and Tel Aviv, with several intercepted over Israel's commercial capital and Jerusalem-bound projectiles hitting two southern West Bank cities.
Hundreds of rockets have so far caused no Israeli deaths, and many have been intercepted by the Iron Dome missile defence system.
- Centre for disabled hit -
An attack on the northern Gaza Strip hit a centre for the handicapped, killing two disabled women and wounding four, the centre's director said.
"They didn't understand what was happening and they were so frightened," Jamila Alaywa said of those inside the care home.
"They fired the rocket and it hit us without any warning."
Other targets included a bank, the homes of Hamas leaders and a mosque that Israel said was used to store weapons.
Two of Haniya's nephews were among the dead in one strike, residents said.
Three rockets fired from Gaza, apparently at Jerusalem, fell short, hitting Hebron and Bethlehem, the army and Palestinian security sources said, with no reports of casualties.
Of four fired later at Tel Aviv, three were intercepted above the city and another hit open ground south of it, the army said, with Hamas having warned of the attacks an hour before.
Hamas has fired several rockets at Jerusalem and Israel's commercial capital Tel Aviv since Tuesday, most of which have been intercepted.
Well over 500 projectiles have struck Israel, the army says.
Amid international efforts to mediate a truce, Egyptian president Abdel Fatah al-Sisi's government was in touch with both sides, his spokesman said.
Sisi met Middle East Quartet envoy Tony Blair in Cairo on Saturday to discuss the crisis, and later warned against escalation causing further loss of "innocent lives".
In Washington, the White House has said it is willing to "leverage" its relationships in the region to bring about a ceasefire.
The chief diplomats of Britain, France, Germany and the United States are due to discuss how to achieve a truce when they meet in Vienna on Sunday.
Italian Foreign Minister Federica Mogherini plans to visit Israel and the Palestinian territories from July 14-17 and Egypt on July 18, her ministry said.
Iranian Foreign Minister Mohammad Javad Zarif, in a taped interview with US broadcaster NBC, urged Washington to use the UN to stop the Israeli strikes.
- Little sign of compromise -
However, there has been little sign that either side is interested in an immediate end to the hostilities.
On Friday, Cairo said its efforts to mediate a return to a 2012 ceasefire agreement "have met with stubbornness".
And Israeli Prime Minister Netanyahu told a Tel Aviv news conference he would not end the military campaign until he achieved his goal of stopping the Hamas fire.
"No international pressure will prevent us from striking, with all force, against the terrorist organisation which calls for our destruction," he said.
Haniya said: "(Israel) is the one that started this aggression and it must stop, because we are (simply) defending ourselves."
The latest conflict unfolded after last month's kidnap and murder of three young Israelis in the occupied West Bank and the brutal revenge killing of a Palestinian teenager by Jewish extremists.
Israel cracked down on Hamas, though the Islamist group declined to confirm or deny involvement in the abductions, and Gaza militants hit back with intensified rocket fire.
Israel says preparations are under way for a possible ground incursion, with tanks and artillery massed along the border and some 33,000 reservists mobilised out of 40,000 approved by the cabinet.
Foreign Minister Avigdor Lieberman has said he expected a political decision on a possible ground operation to be taken by Sunday.