Defence Minister Ehud Barak is considering leaving Labour to join Binyamin Netanyahu's government as an independent MK, according to party sources.
Mr Barak mobilised business leaders, former Supreme Court judges and retired senior IDF officers to lobby his colleagues in an attempt to forge a party-wide coalition with Likud. So far, however, Labour's Knesset members remain overwhelmingly opposed.
"There are rumours that Barak has support from the party for coalition talks," said MK Danny Ben-Simon. "But the rumours are being put out by Barak's political advisors. In the faction meeting, people spoke out very clearly in favour of going to the opposition."
Labour MKs fear that their leader may reach a deal with Mr Netanyahu behind their backs. He could then convene the 1,500 members of the party's central committee and ask them to approve the deal, despite the opposition of the parliamentary faction. "That would put us in a very difficult situation," said Mr Ben-Simon. Some members of the party are already talking of a possible split, which could see the more radical MKs leaving to join the left-wing Meretz party.
Mr Barak has another option which Labour members fear even more - to leave the party altogether and join the Netanyahu government as an independent MK to serve as defence minister. Veteran Labourites remember the precedent set by Moshe Dayan, who left the party in 1977 to serve as Menachem Begin's defence minister. More recently, the departure of Shimon Peres to Kadima four years ago still rankles.
"Everyone who knows Barak is aware that he is always considering a thousand options," said Mr Ben-Simon. "I will not be surprised if one day he arrives at a party meeting and tells us that he is leaving, for the good of the nation."
The prime minister-designate is anxious to include a mainstream party in what is shaping up to be a very right-wing coalition. Despite Labour winning only 13 seats, Mr Netanyahu is willing to give them five cabinet places, including defence and justice.
Kadima's parliamentary faction voted on Sunday not to enter into coalition negotiations.