An alliance between Israeli Prime Minister Benjamin Netanyahu's Likud party and Avigdor Lieberman's ultranationalist Yisrael Beitenu has angered many within the premier's party, commentators said on Sunday.
Late last week, Netanyahu and his foreign minister said their two parties would run on a joint list in the January general elections in a move likely to see them lead the next coalition government.
Netanyahu's rightwing party, which holds 27 of the 120 seats in the Knesset, will on Monday evening in Tel Aviv at the Likud Convention vote on the merger with Yisrael Beitenu, which holds 15 seats.
But the move has sparked widespread dissent within Likud with many fearing it would hurt the party, Sunday's newspapers reported.
"Half the Likud ministers either opposed to the merger with Yisrael Beitenu or have doubts about the agreement," said the top-selling Yediot Aharonot, noting the announcement had sparked "fierce opposition" within the party.
Figures from a survey of Likud voters released at the weekend by Israel's Channel 10 television showed 26 percent were against the move, while 58 percent were in favour. And 22 percent said they did not intend to vote for the united list in January.
It also showed similar sentiments among Yisrael Beitenu voters, with 35 percent saying they were against the deal, while 51 percent supported it.
"The house is burning," a senior Likud figure told Haaretz. "There's a smell of explosives in the air. Many loyal voters told us: 'We have no intention of voting for this thing'."
Another unnamed minister who spoke to Maariv newspaper was clearly bitter over the deal.
"Netanyahu's put us in an impossible situation," he said. "He didn't consult with us and didn't take us into account. He worked over our heads, as if Likud were only his," he said.
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"He gambled on our future just in order to ensure himself a third term in power."
With the party's 3,700 members expected to turn out for the Likud Convention, Public Services Minister Michael Eitan was reportedly collecting signatures from the central committee members in order to force a secret ballot on the issue.
"The merger is a mistake because it repels voters. Some of Lieberman's voters don't like Netanyahu, and some Likud voters don't like Lieberman," he told Israel HaYom, which is close to the Israeli leader.
"Running separately could have led to a larger bloc after the election," he said.
But US political consultant Arthur Finkelstein, who was involved in brokering the deal, said the unified list would receive at least the 42 seats they already have -- as well as another two or three on top of that.
"The union will not only result in a stronger political coalition -- because it will be easier to win the election with a united right bloc -- it also makes Israel safer and more stable. It's good for them, it's good for the country and good for the Jewish people," he told Channel 2 television late on Saturday.
But veteran Yediot columnist Sever Plocker disagreed.
Netanyahu and Lieberman, he wrote, "are looking for ways to rule the country by means of a single party. To force their will and to coerce the ministers into accepting their will as divine scripture.
"What they really want is more and more control. That is why they merged. But that could also be why they will fail: larger parties swallowing up smaller parties won't do away with the differences of opinion; rather, it will only intensify them."
Polls taken over the last fortnight have consistently shown that Netanyahu and the rightwing and religious parties allied with him are set for a comfortable victory, given the fragmentation of the opposition and the lack of alternative candidates for the premiership.