Egyptian President Hosni Mubarak on Thursday urged restraint and UN chief Ban Ki-moon expressed concern as Gaza militants fired off another barrage of mortars and rockets against Israel on Thursday and the Israeli cabinet approved a broad invasion of Hamas-ruled Gaza as soon as winter rains subside. Israeli defense officials said the invasion would likely begin with surgical airstrikes against rocket launchers and continue with a land incursion. Te operation won't be launched until the skies clear, they added. Israeli Defense Minister Ehud Barak warned that Gaza militants would pay a “heavy price” if they continued to target Israel. But he decided to open the crossings between Israel and the Gaza Strip on Friday “to allow the transfer to Gaza of vital humanitarian aide,” his office said. The minister's decision followed intense international pressure – particularly from Egypt – on Israel to ease its blockade of the Gaza Strip, where most of the 1.5 million population depends on foreign aid, Israeli television said. Mubarak made the plea for restraint during talks in Cairo with Foreign Minister Tzipi Livni, saying he expects Hamas militants to immediately halt their fire on Israel. “Egypt has made clear that there should be restraint and no escalation and an alleviation of the humanitarian situation,” Egyptian Foreign Minister Ahmed Abul Gheit said, urging Israel to refrain from “collective punishment.” Egypt plans to invite leaders of Palestinian groups for talks “one after the other,” Gheit said ,but expressed pessimism that a new truce could be achieved. Livni's visit came after a six-month truce between Israel and Hamas expired last Friday and two days after Israeli troops killed three Palestinian militants along the Gaza-Israel border fence. Egypt had brokered that truce. Livni vowed to strike back at Hamas. “Enough is enough. The situation is going to change,” Livni said after meeting Mubarak. “Yesterday's escalation was unbearable,” said said after Gaza militants on Wednesday hit Israel with their biggest rocket barrage in six months to avenge the killing of three fighters from the Islamist movement. Israel left Gaza in 2005 after a 38-year occupation, but still controls its border crossings. Hamas militants seized control of Gaza in June 2007. UN chief Ban Ki-moon expressed concern about the situation, condemned the rocket attacks and also called for an urgent easing of humanitarian conditions in the Gaza Strip. A Dialog survey published in the Haaretz daily on Thursday indicated Israelis were slightly more opposed to an incursion that would put Israeli soldiers' lives at risk. The poll, which surveyed 475 people and had a margin of error of 4.5 percentage points, found 40 percent of Israelis in favor of an operation and 46 percent opposed to it.ing, en route to the West Bank town of Bethlehem for Christmas Day celebrations.