Recent poll found that united list would receive 23 mandates.
Former justice minister Tzipi Livni and Head of the Labor party Isaac Herzog announced a unity deal at a Tel Aviv press conference on Wednesday evening, announcing that if they win the two leaders would rotate the prime minister position.
"When we get the mandate from the president, I will be the prime minister for the first two years and Tzipi Livni will be prime minister for the following two years," Herzog said at the press conference.
"We\’re uniting for the good of the country, for the better future of our children and grandchildren. We can only win together," he said.
Livni said Herzog will be a terrific prime minister. She noted that their fathers served in the Knesset in rival parties.
A general election in Israel is scheduled for March 17, 2015.
A joint list containing both Herzog and Livni would trump Prime Minister Benjamin Netanyahu\’s Likud party in elections to the 20th Knesset, according to a poll published Monday.
The Knesset Channel poll found that a list containing Herzog and Livni would receive 23 mandates, while the Likud would receive only 21 mandates.
Were Livni to run alone with her Hatnua party she would fail to pass the electoral threshold, the poll found. Labor, with Herzog as its leader, would receive only 17 mandates without Livni, according to the survey.