Israel today threatened further military action to weaken Hamas in Gaza as its troops withdrew after a week-long offensive that killed more than 100 Palestinians.

The Israeli prime minister, Ehud Olmert, said more strikes were likely against militants firing rockets from Gaza. The declaration comes despite widespread condemnation of Israel's action.

"We are in the midst of a combat action. What happened in recent days was not a one-time event," an Israeli official quoted Olmert as telling a parliamentary panel. "The objective is reducing the rocket fire and weakening Hamas."

Palestinians in Gaza can expect a respite as the US secretary of state, Condoleezza Rice, arrives in the region to try and salvage what remains of a US push for peace that began in November.

A senior Israeli government official said there would be a "two-day interval" for Rice's visit. She is to hold talks in Jerusalem and the West Bank city of Ramallah tomorrow and Wednesday on moving negotiations forward.

The US president, George Bush, said in November at the Annapolis conference that he hoped agreement on a Palestinian state could be reached this year. But the deadliest fighting since the Palestinian uprising of the 1980s has made Rice's task much harder.

Mahmoud Abbas, whose western-backed forces lost control of Gaza to Hamas in June, said he would not resume talks with the Israeli prime minister, Ehud Olmert, until Israel stopped its attacks.

"The situation is grave and what resulted from the Israeli aggression was unprecedented since the 1967 war of Israeli occupation," said the Palestinian prime minister, Salam Fayyad.

The Palestinian health ministry said 116 Palestinians were killed in the Gaza offensive. Militant groups said about half were civilians. Fayyad put the death toll at 110 and said 250 people were wounded.

Many of the civilian casualties came when Israeli missiles fired by helicopters, jets and unmanned drones hit buildings and homes that the army said were used by militants.

Overnight, Israel carried out air strikes in the Gaza Strip. Three militants died, according to medical workers and Hamas. The army said it had targeted workshops making rockets.

Two Israeli soldiers were killed in the offensive and on Wednesday an Israeli civilian was killed by a rocket, the first such death since May.

The UN secretary general, Ban Ki-moon, condemned Israel for using "excessive force" and called on Palestinians to halt their rocket attacks. The US called for Israeli restraint. "We're encouraging Israel to exercise caution to avoid the loss of innocent life," a US state department spokesman said after Rice spoke to Abbas yesterday.

A White House spokesman said: "The violence needs to stop and the talks need to resume."

As Israel withdrew its troops, a spokesman for the Hamas armed wing declared victory and vowed it would continue the attacks. "The enemy has been defeated," said the Hamas spokesman. A senior Hamas official, Sami Abu Zuhri, said: "Gaza will always be a graveyard for the occupation forces."

Despite days of Israeli assault, Gaza militants continued firing rockets. Three landed in Ashkelon, a city of 120,000 people, one hitting an apartment building, Israeli rescue services said. No casualties were reported.

The Israeli deputy prime minister, Haim Ramon, told army radio: "This operation has run its course. The main goal of the Israeli government... is to end the firing at targets in the south. There were dozens of deaths among the Hamas terorrists - this is certainly deterrence."

The Israeli defence minister, Ehud Barak, said a full-scale invasion was still possible, and Israel might try to bring down Hamas. "We will use force to change the situation," Barak told a meeting late yesterday of security commanders, according to a statement from his office.

Since the Annapolis conference there has been little movement in talks between Olmert and Abbas. The Palestinians have complained that Israel has done little to remove checkpoints that hamper movement and trade, and fighting between Hamas and Israel has escalated.