Israeli opposition Labor party leader Isaac Hertzog and centrist former justice minister Tzipi Livni on Wednesday announced an alliance to contest snap general election in March.

Israeli opposition Labor party leader Isaac Hertzog and centrist former justice minister Tzipi Livni on Wednesday announced an alliance to contest snap general election in March.

"When we receive the mandate... I shall serve as prime minister for the first two years and Tzipi Livni will serve as prime minister for the second half" of the four-year term, Hertzog said at a televised news conference.

"Today the Zionist centre has risen against the parties of the extreme right," said Livni, formerly Israel's chief “peace” negotiator with the Palestinians, who was fired from government last week by Prime Minister Benjamin Netanyahu, who accused her of working against his right-leaning coalition from within.

She began her political career in Likud before following the late Ariel Sharon when he founded the Kadima party, then setting up her own HaTnuah before the last election.

She said that today's Likud has been taken over by the far-right.
"The extremists... are turning our country into an isolated state, closed and alienated from its own citizens."

"I am here to produce the force-multiplier that will replace the government of Israel," she said.

Polls published on Tuesday said an alliance between Labor and Livni's HaTnuah party could nudge Netanyahu's Likud from power.

A survey by parliament TV, published by Maariv newspaper, said that a partnership could win 23 seats in the 120-member Knesset, while Likud was projected to win 21.

Another poll by news website Globes put the figure at 24 for Labour-HaTnuah and 23 for Netanyahu's party.