Labor Party leader Shelly Yachimovich ended speculation about joining a Likud-led coalition by stating she will either lead the next government, or lead the opposition to it.

“There are only two possibilities,” Yachimovich declared at a press conference at her party’s headquarters in Tel Aviv on Thursday. “Either the Labor Party under my leadership forms the government, or we will lead the opposition.”

It was the first time that Yachmovich publicly nixed joining a Likud-led coalition.

The Labor leader explained that until now she had not discounted the possibility of forming a government with rival Likud under Prime Minister Benjamin Netanyahu, but recent changes in the Likud party line have put the option out of the question.

In particular, the inclusion of right-wing hardliner Moshe Feiglin on the Likud list and the joint campaign with Yisrael Beytenu under Avigdor Liberman, whom she labeled “corrupt,” have proved too much for her to bear.

“The Likud is no longer the Likud that we used to know,” Yachimovich said. “It is Feiglin on one side and Liberman on the other. That is taking things to an extreme in every possible way.”

Yachimovich explained that the decision to reject joining a Likud coalition was made at a party meeting attended by Labor Knesset members and election candidates. Among the deciding factors, she said, was the clarification of planned budget cuts by the Likud that will bring “a social hell and economic chaos.” Yachimovich went on to say that the Likud did not deny the allegations.

Yachimovich’s statements drew harsh responses from rival politicians.

Chairman of the Likud Election Committee MK Gilad Erdan retorted: “Just to make it clear: Yachimovich is knowingly lying. She received a blanket denial to her fairy tales about budget cuts that are purely a product of her wild imagination.”

Yisrael Beytenu responded to the corruption allegation by saying that Labor’s members also have a sordid history. ”Before Yachimovich dares to say anything she should take a look at her own party list.”

The party went on to name Labor members Moshe Mizrahi, who was dismissed from his position with the police due to illegal wiretapping of Liberman, and Isaac Herzog, who maintained his right to silence as police investigated possibly illegal election funding of the now defunct One Israel party, at the time under Defense Minister Ehud Barak. The probe ended in 2006 without indictments.

Yisrael Beytenu also criticized Yachimovich and her party member Miki Rosenthal, both former journalists. ”They didn’t even wait half an hour before switching from journalism to politics, breaking the rules of etiquette. They are the last [party] list that can preach ethics,” the statement said.

Yair Lapid, the chairman of the Yesh Atid party, charged that Yachimovich was “hysterical.”

“In a fit of stress and hysteria, Yachimovich decimated the chance of establishing a Zionist, non-messianist government that won’t transfer billions to yeshivas and isolated settlements,” Lapid said in a statement.

He asserted that, if if his party joins a coalition under Netanyahu, it “won’t sit as a wallflower in a government comprising Haredim and the messianist right.”

According to Maariv, Meretz MK Ilan Gilon joked that Yachimovich’s turnabout represented progress of a sort.

“If Yachimovich continues in this direction she will go back on her support for funding the settlements, join the ranks of human rights in Israel, and even agree to be called left-wing,” Gilon said.

Last week the firmly left-wing Meretz party declared a binding commitment to stay out of a Likud coalition.