In a last-ditch effort to prevent the 11-MK Israel Beiteinu faction's departure from the coalition, Prime Minister Ehud Olmert met with the party's chairman and Strategic Affairs Minister Avigdor Lieberman on Tuesday afternoon. Lieberman has threatened to leave the government due to Olmert's plans to negotiate with Palestinians on core issues. Lieberman is expected to announce his decision on Tuesday evening. Close associates of the prime minister said Tuesday's talks were conducted in a "good atmosphere" and that Olmert provided the Israel Beiteinu chairman with "all the clarifications he required," Army Radio reported. On Monday, sources close to Olmert said the prime minister would ask Lieberman to keep Israel Beiteinu in the coalition because of key decisions that would be made regarding Iran. "We are in the middle of important meetings in the security cabinet on key issues that you initiated," the sources said Olmert would tell Lieberman, referring to Iran. "There is no concrete reason for you to go. I have discussed core issues with Palestinian Authority President Mahmoud Abbas for months. You can still have more impact from the inside." Lieberman's associates said such talk would not be enough to keep him in the government. They said the fact that he had already planned a noon press conference at the Knesset on Wednesday was a good sign that he had decided to leave unless Olmert surprised him with a persuasive argument. "If Olmert said the talks on the core issues were only for show or if he promised not to remove an outpost until Kassam rocket attacks stopped, that might change his mind," a Lieberman associate said. If Israel Beiteinu does indeed leave the government, it would leave Olmert with a fragile coalition of 67. At the start of Monday's Knesset plenum session, Israel Beiteinu showed its displeasure with the government by walking out on a no-confidence motion regarding Israel's negotiations with the Palestinians on core issues. Sources close to Lieberman said the party head had received the impression that Olmert concluded that Labor and Israel Beiteinu could no longer exist in the same coalition and that he chose to keep Labor at Lieberman's expense. They cited Olmert's statements to the Knesset Foreign Affairs and Defense Committee Monday about the need to negotiate the core issues of the conflict and his statements Sunday to Kadima ministers about outposts remaining being a disgrace. Olmert's associates said he had not intended to push out Lieberman but privately they admitted that if Israel Beiteinu left, it would give the diplomatic process a boost and make it more likely that Defense Minister Ehud Barak would keep Labor in the coalition. Sources close to Barak said Israel Beiteinu's departure would indeed increase pressure for Labor to stay, but that Lieberman would not impact Barak's decision about whether to keep his promise to remove Labor from the coalition upon the Winograd Report's publication on January 30. Channel 1's Ayala Hason reported Monday that if the Winograd report ended up being extremely critical of Olmert, Barak would give Kadima six weeks to elect a new leader. If Kadima would refuse, Barak would bring down the government and force an election. Welfare and Social Services Minister Isaac Herzog, who is number two on the Labor list, said Lieberman leaving the government would give Labor more justification to stay. "I'm in principle against breaking up governments," Herzog said. "I think [if the government fell] those who will suffer most are those who are silent populations - the weak and needy, those who are shunned away from the general knowledge of the public because they do not offer enough ratings or sex appeal." Opposition leader Binyamin Netanyahu urged both Israel Beiteinu and Shas on Monday to leave the coalition immediately to prevent concessions that could harm Israel's security. Speaking to the Likud faction, Netanyahu warned that Olmert's government would give up half of Jerusalem and restore Israel to pre-1967 lines. "The Olmert government has conceded on the first stage of the road map, which conditioned the start of negotiations on a complete cessation of terror," Netanyahu said. "Now concessions are being made that endanger our security. The parties in the coalition from the nationalist camp, our friends Shas and Israel Beiteinu, understand the dangers. I call upon them to reach the necessary conclusions and stop these processes by leaving the government now." Ruth Eglash and Sheera Claire Frenkel contributed to this report.