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Two years since he was elected to the post of Labor party leader, Gabbay announced on Tuesday that he would not run in the July 2 Labor leadership race.
In a victory for Labor leadership candidate Amir Peretz and Party Secretary General Eran Hermoni, the party will ask members in what manner they wish elections be held.
Gabbay had resisted calls to resign since he led Labor's fall from 24 to six seats in the April 9 election.
The proposal to keep the same list of Knesset candidates but with an as yet unselected new leader is expected to be approved in Wednesday's Labor convention.
Meanwhile, Blue and White made a series of decisions on Wednesday about how to run its campaign.
Gabbay said his party's executive committee would meet Tuesday to approve his proposal to hold the leadership race "as soon as possible."