Peretz said he would take on the role of mediator to build such a government and then to expand it by bringing in other parties afterward.
In a Facebook Live post on Friday afternoon, Netanyahu said Peretz had confirmed his repeated warnings that if given a chance to form a government, Blue and White leader Benny Gantz would build a left-wing coalition with the assistance of Joint List faction head Ahmad Tibi.
"Such a government would be a danger to Israel's security," Netanyahu said.
Peretz replied that "the real danger to Israel was having a prime minister with three criminal indictments dragging Israel to a fourth election." He accused Netanyahu of risking Israel's security interests in order to evade prosecution.
Yisrael Beytenu leader Avigdor Liberman denied the story and accused Peretz of lying. He said his party would vote against any government it would not join. "While support grows for Labor-Gesher-Meretz, Yisrael Beytenu needs to realize that they can't form a government with six seats and refuse to join with the other parties." the group of parties said responding to Liberman's claims.
Earlier on Friday, Netanyahu toured Jerusalem's Mahane Yehuda Market while Labor candidates toured downtown Jerusalem.