U.S. Secretary of State Condoleezza Rice is en route to the Middle East following days of violence that has prompted Palestinian President Mahmoud Abbas to suspend peace talks.
Israel pulled its ground troops out of northern Gaza early Monday but continued to strike targets using aircraft.
The campaign, which has left some 117 Palestinians dead, was in response to rocket fire into Israel by Hamas militants.
One Israeli was killed last Wednesday by a rocket attack. Two Israeli soldiers have also been killed in fighting in Jebalya.
Despite the Israeli offensive, militants in Gaza continue to launch rocket attacks at parts of southern Israel -- including Ashkelon, with a population of 120,000.
Three rockets hit Ashkelon early Monday but no casualties were reported, Israeli rescue services said.
"The issue for Israel now is the debut of longer-range missiles... that they believe were smuggled into the Gaza Strip through the Rafah border when Hamas knocked it down in January," CTV's Janis Mackey Frayer said from Jerusalem.
"...From Israel's point of view there are some 200,000 Israelis who are now within range of these longer-distance rockets."
Israel said Monday that the troop pullback was only temporary.
"We are acting and we will continue to act in a way that is painful and effective, that will bring maximum results in terms of halting terror," Israeli Prime Minister Ehud Olmert told members of his Kadima Party.
Peace talks
Rice is scheduled to meet with officials on Tuesday to help promote the resumption of peace talks.
"Certainly we do want to see negotiations resume," U.S. State Department spokesman Tom Casey told Reuters. "All this points out the need for there to be progress in the negotiations and ultimately have a two-state solution. That's the answer to the violence that we've seen.
"We regret any loss of innocent life that has occurred, and certainly hope that the actions will end in the near future," he said, referring to both sides.
On Sunday, Abbas ordered the suspension of talks with Israel but he did not declare them dead.
"For the time being, the negotiations are suspended because we have so many funerals," said Palestinian negotiator Saeb Erekat.
United Nations chief Ban Ki-Moon has accused Israel of "disproportionate and excessive use of force that has killed and injured so many civilians, including children."
Olmert rejected the criticisms in a meeting with his cabinet Sunday.
"With all due respect, nothing will prevent us from continuing operations to protect our citizens," he said.
Olmert said attacking Hamas, the Islamic militant Palestinian group, "strengthens the chance for peace."
With files from The Associated Press
