JERUSALEM — Israel declared a unilateral halt Sunday to its three-week-old military campaign in the Gaza Strip, but prospects for renewed calm were cast in doubt by Hamas leaders who vowed to keep fighting.
After 22 days of strikes that have killed more than 1,200 Palestinians, a third of them children, Israeli Prime Minister Ehud Olmert declared that the Hamas rulers in the Gaza Strip had been dealt a decisive blow.
Bolstered by international support to prevent Gaza militants from rebuilding their arms smuggling tunnels to Egypt, Olmert announced that the Israeli military would halt its attacks at 2 a.m. Sunday, Jerusalem time. However, Olmert gave no timeline for withdrawing the soldiers and said that they'd remain in Gaza until the situation stabilized.
"If our enemies decide that the blows they have already suffered are not enough and they wish to continue fighting, Israel will be ready for that scenario and will feel free to continue responding with force," Olmert said during a late-night news conference at Israel's military headquarters in Tel Aviv.
"If Hamas decides to continue its wild terrorist attacks, it may find itself surprised again by the State of Israel's determination," Olmert warned. "I do not suggest that it — or any other terrorist organization — test us."
Israeli leaders decided to declare a unilateral truce after concluding that the Hamas leadership was too fractured to negotiate over a cease-fire deal being brokered by Egypt, according to diplomats.
Without any Egyptian-backed assurances from Hamas, Israel is gambling that the Islamist group's Gaza leaders will be so afraid of a resumption of the Israeli attacks that they'll order a complete halt to rocket fire aimed at southern Israel and attacks on the soldiers in Gaza.
"Hamas has been begging for Israel to let up," said one Israeli briefed on the cease-fire discussions.
Gaza militants kept up their rocket strikes on Israel in the hours leading up to the announcement. Palestinians fired more than two dozen rockets into Israel, but no one was seriously injured.
Since Israel launched the military campaign on Dec. 27, four Israelis have been killed by Palestinian rocket fire and nine Israeli soldiers have died fighting in Gaza.
While Hamas has been dealt a severe blow in Gaza, its leaders are publicly vowing to keep fighting.
Hamas leader Osama Hamdan in Beirut said that the group was under no obligation to defer to Israel's demands and bring Gaza attacks to an end.
"If there are no real arrangements discussed between sides, no one has to ask anyone to do anything," Hamdan told Al Jazeera English television before Olmert announced the unilateral truce. "They have finally to understand they have to talk to the resistance."
Israel refuses to talk to Hamas until the militant group renounces its pledge to destroy Israel.
The Israeli Security Cabinet decision to declare a halt to the strikes came hours after its military hit another United Nations compound in Gaza where hundreds of Palestinians were seeking refuge. The early-morning strike killed two boys, aged 5 and 7, as the U.N. staff was working to evacuate 1,800 Palestinians that had taken shelter in a U.N. elementary school in the northern Gaza Strip town of Beit Lahiya, said Chris Gunness, spokesman for the U.N. refugee agency.
Saturday's attack sparked the strongest criticism yet from John Ging, the head of the U.N. refugee agency, who joined with international human rights groups that have called for Israel to be investigated for war crimes.
U.N. Secretary-General Ban Ki-moon called the strike "outrageous" and noted that Israeli leaders had assured him during his recent visit that U.N. posts in Gaza would be protected.
Ban called for an investigation and demanded punishment for those responsible for the "appalling acts."
The Israeli military said it is still looking into the incident, the latest in a string of attacks on U.N. facilities.
In a statement about attacks on U.N. compounds, a high-rise that houses international media offices and a major Gaza City hospital, the Israeli military said "in all the above-mentioned incidents, Israeli forces were fired on from inside or adjacent to these locations, and that the IDF was responding to these attacks."
Ging has consistently denied Israeli military allegations that militants used U.N. property to launch attacks. Gunness also noted that Israeli officials had given contradictory versions of what prompted Israeli strikes on U.N. facilities.
"Their credibility on these allegations is hanging in rags," Gunness said.
In a sign of the continued international concern over the conflict, leaders from around the world accepted invitations from Egyptian President Hosni Mubarak to attend an emergency summit on Sunday in Sharm el-Sheikh.
Among those planning to attend are Ban, French President Nicolas Sarkozy and British Prime Minister Gordon Brown.
Britain, Germany and France all have pledged to offer naval support to help Israel patrol the Mediterranean coast to ensure that no weapons are smuggled into Gaza.
As Israeli leaders were preparing to consider the cease-fire, Mubarak called on Israel to declare an immediate truce and pull its forces out of Gaza.
In a speech to his nation, Mubarak firmly rejected an idea floated by Israeli leaders to dispatch an international force to crack down on arms smuggling under Egypt's border with Gaza.
"I say that this is a red line, and I will not allow it," Mubarak said.
Israel has made cracking down on Hamas arms smuggling a central goal of its military campaign in Gaza. The Israeli military has repeatedly hit the Gaza side of the border and estimated that it's destroyed 80 percent of the estimated 250 tunnels.
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