An operation will be launched against Hamas in the Gaza Strip even if the terror group heeds an Egyptian request and reduces its rocket attacks against Israel, senior defense officials said Monday. Hamas officials said the group had agreed to a 24-hour cease-fire after a warning from Egypt that Israel would begin assassinating Hamas leaders if the rocket attacks continued. A senior Hamas official in the Gaza Strip told The Jerusalem Post that Egypt had relayed the message Sunday night. He said that Egyptian intelligence chief Gen. Omar Suleiman had contacted Hamas leaders there and in Damascus and urged a halt to the attacks so as not to give Israel an excuse to launch a massive military operation. "The Egyptians told us that Israel is planning to assassinate a number of Hamas leaders," the official said. "They advised us to do something to calm the situation before it's too late." The 24-hour cease-fire was to begin Sunday night. The initial cease-fire was allowed to lapse on Friday morning. Senior Hamas leader Mahmoud Zahar was quoted as saying Tuesday that the group was willing to extend the temporary cease-fire if Israel abides by the terms agreed upon in June. Speaking to the Egyptian newspaper Al-Aharam, Zahar said Hamas would hold a "situation assessment" to discuss the 24-hour truce. "If [we see] that the cease-fire has had good results, it's likely that the truce will continue," he said. Zahar told Channel 10 on Monday, "The price is the lives of the Palestinian people." He demanded that Israel allow regular shipments of food and fuel into the Gaza Strip and that it cease its military actions both there and in the West Bank. Israeli officials said they did not believe Hamas would completely cease its rocket attacks against the western Negev but explained that the combination of an Egyptian request and Israeli threats to invade Gaza was having an effect. "Hamas does not want us to invade Gaza," one official explained. "They are hoping that because of the elections we will not invade and that they will be able to put pressure on us with the rocket attacks and... get better conditions in a new cease-fire." Defense Minister Ehud Barak held a meeting on Monday to review the use of artillery in a potential conflict with Hamas. Ministry legal experts have recommended that Israel avoid firing shells into populated areas used to launch Kassam rockets. Ayman Taha, a Hamas spokesman, said that an extension of the cease-fire was contingent on an end to Israel's blockade and attacks. He said Hamas had agreed to a temporary cease-fire to give the Egyptians a chance at mediation. Taha was quoted by Agence France Press as threatening to resume suicide bombings inside Israel. "It is our right as an occupied people to defend ourselves from the occupation by all means possible, including suicide attacks," he said. Palestinian Authority officials in Ramallah claimed that the renewed cease-fire arose from Hamas's fear that Israel would reinstate its policy of targeted killings. One official described Hamas leaders as "cowards," saying their only concern was their personal safety and not the well-being of Gaza residents. Taher a-Nunu, a spokesman for the Hamas government, said his movement agreed to a 24-hour cease-fire in return for the re-opening of border crossings and a halt to Israeli "aggression." He added that Egypt had resumed its efforts to extend the cease-fire. "The Palestinian factions in the Gaza Strip, including Hamas, have accepted the latest Egyptian initiative to call a cease-fire," a-Nunu said. He did not rule out the possibility that the 24-hour lull would be extended. Like many Hamas officials, a-Nunu said the group refused to take Israel's threats of a major military operation seriously. "These threats are related to the election campaign inside Israel," he said. "They are also designed to conceal the big crime - namely the unjust siege and the suffering of our people in the Gaza Strip." In response to reports that Israel was planning to overthrow the Hamas regime, a-Nunu said that neither Israel nor the US would be able to get rid of Hamas. "Hamas is not just a movement or a government," he said. "Hamas is in the heart of every Palestinian. It's a popular movement that has a strong presence among the masses." Fawzi Barhoum, another Hamas spokesman, called Israeli threats "psychological warfare." "Israel wants to extort us so that we would agree to a cease-fire without gaining anything in return," Barhoum said. "Israel is offering us calm in return for calm, and this is unacceptable. They don't want to lift the siege and include the West Bank in the cease-fire agreement." Ali Barakeh, a Hamas official in Gaza City, ruled out the possibility that Israel would invade the Gaza Strip. "The Israelis fear the consequences of such an action," Barakeh said. "They know that they will pay a heavy price."