The UN chief Ban Ki-moon told an emergency Security Council assembly on Thursday that it was more urgent than ever to calm tensions between Israel and the Palestinians, warning of an "all-out escalation" unless action was taken.

"Now is not a time for further incitement or vengeance," Ban said. "We must not let spoilers prevail. We must keep the situation from getting any further out of control."

Ban condemned rocket fire into Israel from Hamas and militants in the Gaza Strip, but also issued a clear message to Israel, saying "the excessive use of force and endangering of civilian lives are also intolerable."

Ban said that many of the roughly 80 Palestinians killed in Israeli airstrikes in recent days were civilians, while more than 300 have been injured and around 900 displaced.

"Once again, Palestinian civilians are caught between Hamas' irresponsibility and Israel's tough response," Ban said.

Israeli and Palestinian ambassadors at odds

Israel's ambassador to the UN, Ron Prosor, and his Palestinian counterpart, Riyad Mansour, both addressed the Council on Thursday; each side blamed the other for the latest escalation in fighting.

Prosor played audio from his cell phone of an Israeli air raid siren into the microphone during his address: "Fifteen seconds, that's how much time you have to run for your life," Prosor said, calling rockets from Gaza a threat to 3.5 million people.

"Condemn Hamas, condemn terrorism and condemn the rocket fire and support Israel's right to defend itself. This is the only way, but the only way to achieve comprehensive peace," Prosor said.

Mansour, on the other hand, said that increased rocket fire into Israel was a response both to airstrikes and to Israeli reprisals following the abduction and killing of three teenagers.

"They started the attack against our people in the occupied territory including Gaza and the rockets started after that," Mansour said after the Council session. He said Palestinians would honor any proposed ceasefire, before claiming "it is obvious that the Israeli side are not interested in a ceasefire and stopping the rockets."

Israeli jets struck 300 Hamas targets in the Gaza Strip overnight, part of an offensive dubbed "Operation Protective Edge" by the Israel Defense Forces. Prime Minister Benjamin Netanyahu has not ruled out a ground invasion of Gaza, also authorizing the mobilization of up to 40,000 reservists.

msh/crh (AFP, AP, dpa, Reuters)