JERUSALEM AND GAZA CITY — The Bush administration gave key backing Friday to an Israeli condition for a cease-fire in the Gaza Strip, supporting a proposal for monitors to patrol Egypt's border with Gaza to prevent weapons from reaching Hamas through an elaborate network of tunnels.
Israeli Foreign Minister Tzipi Livni met with Secretary of State Condoleezza Rice in Washington and signed an agreement on border security and other assurances to destroy tunnels and stop smuggling.
The pact met one of two crucial Israeli demands; the second is that Hamas stop firing rockets into southern Israel.
The deal was approved as U.S. and Middle Eastern diplomats edged closer to accepting an Egyptian-backed cease-fire proposal. Senior Israeli officials said their Security Cabinet would vote on it today. Approval would amount to a cease-fire by Israeli forces, who would leave Gaza only after declaration of an end to the fighting, which has stretched 21 days.
But Hamas political leader Khaled Meshaal contradicted earlier indications that the radical group was prepared to agree to a truce. Meshaal's condemnation of Israel followed heavy Israeli bombardment Thursday that damaged a United Nations compound in Gaza City and killed Hamas' interior minister.
"Resistance can lead to victory, and there will be no cease-fire until our demands are met," Meshaal told Arab leaders at an emergency summit in Doha, Qatar. It was not clear whether Meshaal was posturing or Thursday's violence had hardened Hamas' position. Hamas' demands are that Israel withdraw its troops, lift its blockade of Gaza, and open the Rafah crossing on the Egyptian border.
Other obstacles remained. Israel has long complained that Egypt has been lax in controlling its border with Gaza, and Hamas fired 15 rockets Friday at southern Israel. Israel reported carrying out at least 40 airstrikes in Gaza.
Israeli TV broadcast an anguished appeal for help from a Hebrew-speaking Palestinian doctor in Gaza who has been frequently interviewed about conditions there. The doctor called a newscaster at a TV station after an Israeli tank shelled his home Friday and killed three of his daughters.
Overall, fighting was not as intense as a day earlier. And as Israeli special envoy Amos Gilad held another round of negotiations with Egyptian officials, several Israeli officials hinted that a truce was near.
"The conditions have not come to fruition yet," Israeli Security Cabinet member Binyamin Ben-Eliezer said. "But this could well happen late on Saturday and we can put this story behind us."
Mark Regev, spokesman for Israeli Prime Minister Ehud Olmert, said: "Hopefully we're in the final act."
Under the U.S.-Israeli agreement signed in Washington, the United States agreed to help organize international monitors to oversee Gaza border crossings and to provide technical aid to prevent the smuggling of rockets and other arms, officials said. The composition of the monitoring group and other important details remain to be worked out, they said.
"The essential element of this is to inhibit the ability of Hamas to rearm, so . . . you're not back in the same situation six months from now," said Sean McCormack, the chief State Department spokesman.
A separate deal among Americans, Israelis and others will be worked out for control of pedestrian and vehicular traffic across the crossings, he said.
In Gaza City, about 20,000 people, waving green flags and weeping, attended the funeral of Said Siam, the interior minister, who was killed in an Israeli attack Thursday.
"The departure of the martyr Said Siam is a serious hit," said Ahmad Saleem, an accountant who attended the ceremony. "As you can see, crowds of people came to say farewell despite the security situation and the vicious Zionist attacks. This is not the first time that a Hamas leader is assassinated, but Hamas will not be broken."
Another mourner, Khalil Dohal, said: "I hope that the blood of the sheik will stop the massacres in Gaza."
The United Nations reported that the Israeli barrage Thursday was "the most intensive bombardment to date" and that within a 48-hour period 142 Palestinians were killed, including 48 children.
Since the Israeli incursion began Dec. 27, more than 1,100 Palestinians have been killed, a third of them children, according to Gaza health ministry figures that the United Nations deemed credible. At least 13 Israelis -- 10 soldiers and three civilians -- have died.
"I strongly urge Israeli leadership and government to declare a cease-fire unilaterally," said U.N. Secretary-General Ban Ki-moon, who toured the West Bank city of Ramallah. "It's time to think about a unilateral cease-fire from the Israeli government."