The IDF operation in Gaza has killed the last chance for settlement and negotiations with Israel, Damascus-based Hamas leader Khaled Mashaal told Al-Jazeera on Saturday. In a fiery speech on the Arabic news channel, Mashaal condemned Israel's attack on the Gaza Strip, describing it as a "holocaust," and called on the Arabs to continue protesting. "We are living the hardest moments of the resistance now, we want another intifada in Palestine and on the Arab street," Mashaal said. He also addressed the Israeli public, asking, "What have you achieved with this war that you supported, apart from killing children and innocent people? What did you achieve apart from a holocaustâ€¦? You are carrying out a new holocaust, exposing your disgusting faces." The exiled leader went on to present Hamas's demands for a ceasefire: "First, Israel must stop its attacks. Second, its soldiers must immediately leave Gaza. Third, the terrible siege on Gaza must be lifted. Fourth, all border crossings, including the Rafah crossing [to Egypt] must be opened." He went on to say that the group would not "agree to negotiations on a truce while Israel continues to attack us. First of all, [Israel] must stop firing and leave Gaza, and after that we can speak about a truce as we have in the past." He added that Hamas was "coming to every discussion with an open mind." Mashaal's comments came as Hamas teams were in Cairo to negotiate over an Egyptian-proposed ceasefire to end Israeli strikes on the organization. In a direct attack on the military offensive in Strip, Mashaal claimed Operation Cast Lead had failed. "In 15 days of war," he said, "Israel has not been able to meet even one of its goals." "Israel set itself goals that it wanted to achieve in Gaza, but they've all crumbled as time passed. [Israel] attacked from the air, and after that launched a ground offensive, but didn't succeed in meeting its objectives," he said. He called for Israeli leaders to be tried for war crimes against the Palestinians, saying, "I call on Arab countries to work together to bring the Israeli murderers to trial." He also told Arab countries with relations with Israel to "use that card and say to the enemy, stop the attacks or we will end our relationship with you."