The Israeli military is to hold fire for seven hours in parts of the Gaza Strip from 10am (8am BST).
But it said the “humanitarian window” did not apply to areas where troops were still operating.
Israel withdrew most of its ground troops from the Gaza Strip yesterday in an apparent winding down of the nearly month-long operation against Hamas. But fighting continued in parts of Gaza.
The military said it would respond to any attacks during that time.
Ten people were killed in what United Nations and Palestinian officials said was an Israeli air strike near a UN shelter. The United States also lashed out at Israel, saying it was “appalled” by the “disgraceful” attack.
And with Hamas vowing to continue its fight, it remained uncertain whether Israel could unilaterally end the war.
Israel launched its military operation in Gaza on July 8 in response to weeks of heavy rocket fire, carrying out hundreds of air strikes across the crowded seaside territory. It then sent in ground forces on July 17 in what it said was a mission to destroy the tunnels used by Hamas to carry out attacks.
Hamas has fired more than 3,000 rockets into Israel during what has turned into the bloodiest round of fighting ever between the two enemies.
Lt Col Peter Lerner, an Israeli military spokesman, said the bulk of ground troops had been pulled out of Gaza after the military concluded it had destroyed most of the tunnel network.
He said Israel had detected some 30 tunnels that were dug along the border for what he called a “synchronised attack” on the Jewish state.
“We’ve caused substantial damage to this network to an extent where we’ve basically taken this huge threat and made it minimal,” he said. The army had thousands of troops in Gaza at the height of the operation.
In southern Israel, armored vehicles could be seen rolling slowly on to the back of large flatbed trucks near the Gaza border, while soldiers folded flags from atop a tank and rolled up their belongings and sleeping bags.
Lt Col Lerner said, however, that the operation was not over and that Israel would continue to target Hamas’ rocket-firing capabilities and its ability to infiltrate Israel.
While Israeli Prime Minister Benjamin Netanyahu has vowed to press on against Hamas, he is coming under international pressure to halt the fighting because of the heavy civilian death toll.
UN officials say more than three-quarters of the dead have been civilians, including the 10 people killed yesterday at a UN school that has been converted into a shelter in the southern town of Rafah.
UN secretary general Ban Ki-moon called the attack a “moral outrage and a criminal act” and demanded a quick investigation, while the US State Department condemned the strike in unusually strong language.
According to witnesses, Israeli strikes hit just outside the main gates of the school. The Red Crescent charity said the attack occurred while people were in line to get food from aid workers. Gaza health official Ashraf al-Kidra said in addition to the dead, 35 people were wounded.
Robert Turner, director of operations for the UN Palestinian refugee agency in Gaza, said the building had been providing shelter for some 3,000 people. He said the strike killed at least one UN staffer.
“The locations of all these installations have been passed to the Israeli military multiple times,” Mr Turner said. “They know where these shelters are. How this continues to happen I have no idea.”
Inside the UN school’s compound, several bodies, among them children, were strewn across the ground in puddles of blood. “Our trust and our fate are only in the hands of God!” one woman cried.
The Israeli military said it had targeted three wanted militants on a motorcycle nearby and was “reviewing the consequences of this strike”.
In the current round of fighting, UN shelters have been struck by fire seven times. UNRWA, the UN agency that assists Palestinian refugees, says Israel has been the source of fire in all instances. But it has also said it found caches of rockets in vacant schools three times.
Israel accuses Hamas of using civilian areas for cover and says the Islamic militant group is responsible for the heavy death toll because it has been using civilians as “human shields”.