The United States and Israel signed an agreement Friday providing for U.S. technical assistance to help end the flow of weapons to Hamas militants in Gaza. The accord signed by U.S. Secretary of State Condoleezza Rice and Israeli Foreign Minister Tzipi Livni is a supplement to ongoing Egyptian-led Gaza cease-fire efforts.

The memorandum of understanding signed by Rice and Livni commits the United States to provide technical assistance and intelligence support - though not forces on the ground - to assure that the next Gaza cease-fire will be durable and lasting.

The Israeli foreign minister, a candidate for prime minister in elections next month, flew to Washington late Thursday as part of a flurry of diplomatic activity that has given rise to hopes the now three-week-old Gaza conflict will end soon.

Israel has insisted that if it is to end its Gaza offensive, it must have assurances that Hamas will not be able to re-arm through tunnels from Egypt or other means. At a signing ceremony with her U.S. counterpart, Livni said Friday's accord and parallel mediation efforts by Egypt can "create a basis" for an Israeli decision to end hostilities.

"After years of restraint, Israel has shown that it will no longer tolerate attacks on our citizens, and that there will be a high price for terror from Gaza against our citizens," she said. "We have also made clear as have many international leaders, including President Bush and Secretary Rice, that for a cessation of hostilities to be durable, there must be an end to the smuggling of weapons into Gaza. That is why the MOU that we sign today is so important, as a vital component for the cessation of hostilities."

Rice said the continued supply of arms to Hamas and other factions in Gaza is a direct cause of the current conflict.

She said it is incumbent on the international community to prevent the rearmament of the militant Islamic group so that a cease-fire will be fully respected, and the coastal strip does not again become what she termed a "launching pad for rocket attacks on Israeli cities.

At the same time, the secretary reiterated U.S. concern about a humanitarian situation in Gaza she depicted earlier Friday as "quite dire."

"The United States remains deeply concerned, too, about the innocent Palestinians who are suffering in Gaza," she said. "A sustainable end to hostilities, rather than one that collapses within a few days of weeks, is crucial to ending this suffering. In the meantime we are doing all that we can to respond to the humanitarian needs of the population of Gaza. Foreign Minister Livni and I have talked about the need to be responsible to the humanitarian organizations that are working there including the United Nations and the International Committee of the Red Cross."

Rice has said U.S. pressure prompted Israel to accept daily humanitarian cease-fires, and she complained to both Livni and Israeli Defense Minister Ehud Barak after an Israeli shelling that set fire to a U.N. relief supply depot in Gaza on Thursday.

U.S. officials had no immediate details on what U.S. technical assistance to the anti-smuggling effort would entail but said it will not involve deployment of any American military forces.

Rice signed the memorandum on the last business day of the Bush administration, which officially yields power next Tuesday when President-elect Barack Obama is sworn into office. The outgoing secretary said she has briefed Mr. Obama on Gaza diplomacy and discussed the accord over lunch Thursday with incoming Secretary of State Hillary Clinton.