Right-wing Yisrael Beiteinu Chairman Avigdor Lieberman spoke Tuesday night after exit polls predicted 15 seats for the ultranationalist party, saying that he holds the key to forming the country's next government.

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Yisrael Beiteinu scored lower than expected, as early polls predicted 20 seats for Lieberman's party, but nevertheless, the party's rise from the 11 seats it currently holds has made it the third largest party in Israel.

Lieberman said that the strong showing puts him in a strong position to determine who heads the next coalition government. He said he spoke to the two front-runners, Likud leader Benjamin Netanyahu and Kadima leader, Tzipi Livni, and could be persuaded to join either one of them.

Lieberman has stoked controversy by saying Israeli Arabs should pass a loyalty test or lose citizenship. In his speech, he also ruled out any cease-fire with Hamas militants in the Gaza Strip. He declared that the group must be toppled.

Lieberman said that his party will prefer to join a national right-wing government, hinting that he would prefer joining forces with Netanyahu over Livni. "We always said that this is the government we want, and this is the way our hearts lean," he stressed.

Lieberman, who spoke with Kadima and Likud leaders on Monday, added that he does not intend to make any hasty decisions. "Tomorrow the faction will convene, we will appoint a negotiations team and we will make decisions," Lieberman said. "In this election, we set the agenda," he went on to say. "This is our biggest achievement, beyond any other achievement. Yisrael Beiteinu defined what the correct agenda is and what the central issue is ? loyalty."

Former Israeli ambassador to the United States Danny Ayalon, who is No. 7 on the party list, said after the exit polls hit the airwaves that "to be the third largest is very significant."

"We are not a fad party. Since '99 there has been a steady rise and in the next elections we will be able to vie for leadership."

Kitiana Kishnavom, the party's director-general and No. 10 on its list for Knesset, said the secret of Yisrael Beiteinu's success was setting forth to the public its political plan, rather than wasting its time bad-mouthing members of the other parties.

"It is up to Lieberman who will form the next coalition, said Menachem Hofnung, a professor of political science at Hebrew University. "Lieberman has emerged as the kingmaker. He is the winner of these elections and it depends on who he sides with over the next few weeks as to who will be prime minister."

Meanwhile, Likud leader Benjamin Netanyahu phoned Lieberman just after the exit poll results were released, apparently to discuss the formation of a strong right-wing bloc for the future coalition.