Prime Minister Ehud Olmert on Sunday ruled out cease-fire talks with Hamas, calling Israel's battle against the Islamic group a "true war." "Operations against terrorists will continue as they have been conducted for many months," Olmert said. "There is no other way to describe what is happening in the Gaza Strip except as a true war between the Israeli army and terror groups. This war will continue." "Whoever accepts the Quartet principles will, in principle, be a partner for negotiations," Olmert said. Whoever isn't willing to do so, to our regret, cannot be a partner for dialogue with us. This policy will not change." The development came as cabinet ministers discussed the situation in the Gaza Strip and as Hamas officials offered contradictory reports on the possibility of a truce. "We don't object to a truce that ends the siege, but it should not be given gratis, and will not be open-ended," Ahmed Youssef, an aide to Hamas leader Ismail Haniyeh, told the Palestinian Ma'an news agency. He added that the group was prepared to reach a truce with Israel if the latter stops its military campaign in the Gaza Strip and opens crossings into the isolated territory. On Saturday, the Islamist movement officially denied that it was contemplating a hudna[temporary truce] with Israel. Hamas officials accused Israeli and Fatah media outlets of "spreading lies" about a truce to drive a wedge between Hamas and other Palestinian groups and to create divisions inside Hamas. "These reports are completely unfounded," said Ismail Radwan, a top Hamas official in the Gaza Strip. "There is no room to talk about a tahdiyah [period of calm] or hudna while the Israeli aggression continues against the Palestinians and the Gaza Strip." "The enemy understands only the language of resistance," he added. "In any case, a hudna requires consensus from all Palestinian groups. But we are not optimistic about a hudna because the experiences of the past have shown that the enemy does not abide by them." Meanwhile, the London-based pan-Arab Asharq Alawsat newspaper quoted an unnamed Hamas official over the weekend as saying that his movement was "seriously" considering the possibility of declaring an unconditional truce with Israel. "There is a debate inside Hamas and between Hamas and other factions about the hudna and we hope we will succeed," the Hamas official was quoted as saying, adding that his movement would not set preconditions for a cease-fire. The sources said Haniyeh and Syrian-based Hamas leader Khaled Mashaal were in favor of the idea, while Hamas officials Mahmoud Zahar and Said Siam were totally opposed to an unconditional truce. Sources in the Prime Minister's Office in Jerusalem, meanwhile, said that the fact that voices in Hamas had been raised calling for a hudna showed that Israel's policies of applying both military and diplomatic pressure on Hamas were working. The sources said that the PMO had not received any third-party messages from Hamas signaling an interest in a truce. "The party on the Palestinian side that we are dealing with is the Palestinian Authority," the sources said. "The PA is the only Palestinian partner we are speaking with." Fatah officials in Ramallah have exploited the reports of a Hamas interest in a hudna to taunt Hamas and depict its leaders as liars and hypocrites for allegedly negotiating with Israel over a truce. The officials accused Hamas of betraying its followers and ideology by talking to Israel and expressing its readiness for a truce. Ashraf al-Ajrami, the Minister for Prisoners' Affairs in the government of Salaam Fayad, claimed that Israel had informed the PA that it was holding secret talks with Hamas. "Very senior officials in Israel who are connected to the negotiations with Hamas have notified the Palestinian Authority in Ramallah," he said. "The Israelis said they were holding direct and indirect talks with Hamas about a truce because the Hamas leaders want to stay in power." Al-Ajrami said that some Arab parties were acting as mediators between Israel and Hamas, but refused to name them. Herb Keinon contributed to this report.