Yisrael Beytenu chairman Avigdor Liberman rebuffed suggestions that his party’s alliance with the Likud would lead some Likud party members to bolt the allied super-faction, and also alienate rather than attract voters, calling such claims “media hysteria.”

“No one will leave. On the contrary, the alliance will strengthen the party,” he said in an interview to Israel Radio Sunday morning, characterizing the press coverage of the alliance as “grotesque.”

Reports in the past two days in numerous Hebrew media outlets have quoted anonymous Likud ministers, Knesset members and would-be Knesset members calling the alliance a mistake, and predicting that the joint Likud-Yisrael Beytenu list, rather than producing more seats than the two parties’ current 42 (Likud 27; Yisrael Beytenu 15), will lead to a fall in their Knesset representation. A Maariv headline that typified these reports Sunday blared, “Likud ministers: Netanyahu has gambled on our future for his own interests.”

Despite downplaying reports of opposition to the union by Likud members, Liberman toned down his statements from last week, in which he spoke of building a big party that would revive the “historic” national camp, explaining that a full union could take years.

“We plan to continue to function as two different parties that together will both provide stability and bring about much-needed reforms in the fields of national service, coping with poverty and meeting international challenges,” said Liberman.

He said “leftists” and the “media” had greeted news of the alliance with “hysteria” and that their attempts to brand it as a failure, or as constituting an “extremist” bloc, were “pathetic.” The left was always interested in fomenting disunity, Liberman claimed, while the nationalist right always managed to unify at times of crisis.

A snap poll conducted for Channel 10 News Friday showed substantial, though not overwhelming, levels of opposition within Likud and Yisrael Beytenu to the alliance of their two parties and their plan to run together in January’s elections. More polls are expected to be published on Monday.

Though hailed by the two party leaders as a partnership that was sure to benefit both of their parties and the wider Israeli interest, Channel 10′s poll showed 26 percent of Likud voters saying they opposed the alliance, with 58% supporting it. On election day — January 22, 2013 — 22% of Likud voters said they would not vote for the joint list, with 52% saying they would.

Among Yisrael Beytenu voters, 35% said they opposed the alliance, with 51% backing it; and a substantial 32% said they would not vote for the joint list, compared to 40% who would.

The Likud’s Central Committee is set to convene on Monday to approve the partnership. Only one leading Likud figure, MK Michael Eitan, has come out publicly in opposition to it, and he was likely to lose his Knesset seat in the elections anyway. Eitan said Friday that the partnership was “a mistake ideologically,” since the two parties have differing platforms and priorities, and “a mistake practically,” since it would not yield more seats than the two parties would win running separately.

A two-thirds majority is reportedly needed in the Central Committee for the alliance to be approved, and Eitan is leading an effort to arrange a secret vote, and circulating a motion to this effect, so that Likud members would not have to openly defy Netanyahu to oppose the idea. A motion approved by 10% of committee members is needed for a secret ballot to be held.

Dovish Likud MK Dan Meridor is reportedly also considering his future in the party following the union, having expressed concern that the move would take the Likud too far to the right. The alliance is “bad for the Likud,” Meridor has reportedly said, according to Israel Radio. “This is no longer the Likud movement.”

“I was a member of the Likud long before all those people who are criticizing the alliance,” said Liberman, who served as Netanyahu’s bureau chief and the party’s director general in the 90s before founding Yisrael Beytenu. He said that he had held conversations with dozens, if not hundreds of Likud activists, all of whom supported the move.

“There are no electoral fears. Everyone knows it will be a large and serious party. It is only those in the media and on the left who are responding to the union with hysteria,” Liberman said.

Many Likud MKs privately oppose the merger, Channel 10 claimed, naming Deputy Prime Minister Silvan Shalom and MK Miri Regev, neither of whom has said anything publicly to this effect.

Privately, some Likud members are said to believe that Netanyahu panicked into agreeing to the alliance, and that it would backfire. Channel 10 said he was concerned about former prime minister Ehud Olmert returning to politics and heading a merged center-left bloc including Yair Lapid’s Yesh Atid party, Kadima, and former foreign minister Tzipi Livni. Its news report claimed Olmert was now more inclined than he had been to make a political comeback, despite various legal obstacles that could still stand in his way.

Channel 2 analyst Amnon Abramovich suggested Netanyahu had fallen prey to poor polling predictions by conservative political adviser Arthur J. Finkelstein. Insiders claimed Thursday that internal polls had shown a Likud-Yisrael Beytenu alliance could win 50 seats in the 120-member Knesset (currently the Likud has 27 and Yisrael Beytenu has 15). But some in the Likud believe the allied list would win only 32 seats, the TV analysts said.

Abramovich claimed that in 1996, Netanyahu merged the Likud Knesset list with two minor parties, Gesher and Tzomet, because Finkelstein’s polls supposedly predicted their alliance would win 45 seats. In fact the combined list won only 32 seats — which proved just sufficient for Netanyahu to win the elections and become prime minister from 1996 to 1999.

Meanwhile, further details of the agreement emerged Friday. The joint Likud-Yisrael Beytenu Knesset slate will have Netanyahu in first slot and Liberman in second. From there on, the list will reportedly feature two Likud candidates followed by one Yisrael Beytenu candidate — reflecting the approximate strengths of the two parties in the outgoing Knesset. The Likud will choose its candidates in internal party primaries; Liberman heads a panel in his party that chooses its potential MKs.

Netanyahu agreed that Liberman could choose any ministerial position; Liberman said Friday he would likely stick with the Foreign Ministry.

Netanyahu also pledged not to relinquish the Golan Heights in any negotiations with Syria.