Palestinian President Mahmoud Abbas suspended peace negotiations with Israel today, demanding it end a Gaza offensive that has killed more than 100 Palestinians, many of them civilians.
Israel said it was acting in self-defence in the Hamas-controlled Gaza Strip to curb constant cross-border rocket attacks by militants and threatened to intensify its ground and air campaign despite allegations it was using excessive force.
Mr Abbas had ordered "the suspension of negotiations ... until (Israeli) aggression is stopped", a senior aide to the Palestinian leader said in the West Bank city of Ramallah.
But he stopped short of declaring dead the US-brokered statehood talks opposed by Hamas Islamists who seized control of the Gaza Strip from his Fatah movement in June.
Arye Mekel, spokesman for Israel's chief negotiator, Foreign Minister Tzipi Livni, said Mr Abbas's decision was a mistake and expressed hope the talks would resume "in the very near future".
A 21-month-old Palestinian girl and three militants died in the latest fighting in the Gaza Strip, raising the Palestinian death toll in five days of bloodshed to more than 100, medical officials said.
Anti-Israeli demonstrations erupted in the occupied West Bank, where Israeli forces confronting stone-throwers near the town of Hebron shot dead a 14-year-old boy wearing a Hamas headband, witnesses said.
Nine rockets slammed into southern Israel, wounding four people, Israeli ambulance workers said.
"Israel has no intention of stopping the fight against the terrorist organisations even for a minute," Prime Minister Ehud Olmert told his cabinet, facing the new challenge of long-range rockets hitting the major southern Israeli city of Ashkelon.
Earlier, UN Secretary-General Ban Ki-moon accused Israel of using "excessive force". He demanded a halt to air and ground attacks that killed 61 people yesterday, the bloodiest day for Palestinians since the 1980s, and militants' rocket salvoes.
"With all due respect ... no one has the right to preach morality to Israel for employing its elementary right of self-defence," Mr Olmert said.
Mr Abbas designated today a day of mourning.
Mr Olmert said striking at Hamas only advanced the cause of peace, and "the Palestinian leadership -- the one with which we wish to make peace -- understands this".
One Israeli has been killed by a rocket launched from Gaza since the current surge in bloodshed began. Hamas has said such salvoes would stop if Israel abandoned operations in the Gaza Strip and raids against militants in the occupied West Bank.
"We are acting to hit the Hamas infrastructure ... the final target is to bring an end to the firing of Qassams," Defence Minister Ehud Barak said about the crude rockets.
"This will not be achieved in the next two days, but we will continue the activity with all our strength. And we need to prepare for escalation, because the big ground operation is real and tangible," Mr Barak said.
Meeting in emergency session, the UN Security Council said it was deeply concerned about civilian deaths in southern Israel and the Gaza Strip and urged a cessation of violence.
The offensive has taken Israeli troops deeper into the Gaza Strip and in larger numbers than at any time since Israel pulled troops and settlers out of the territory in 2005, 38 years after its capture.