Former Israeli justice minister Tzipi Livni and the center-left parliamentary opposition leader will jointly challenge Prime Minister Benjamin Netanyahu in a March election, political sources said on Wednesday.
They said Livni, whom Netanyahu fired last week as coalition rifts sank his government, would formally announce her alliance with Isaac Herzog of the Labour party later in the day.
Opinion polls predict Netanyahu's rightist Likud party will win the election, taking around 22 of parliament's 120 seats.
Labour is seen taking around 12 seats, a showing that could be improved by teaming up with Livni, whose centrist Hatnuah party has been polling at around 4 seats. One survey this week found that a joint Herzog-Livni list could defeat Likud.
Livni was dismissed along with former finance minister Yair Lapid, leader of centrist party Yesh Atid. They had clashed with Netanyahu over the government's handling of moribund peace talks with the Palestinians and a range of Israeli budget issues.
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