The move follows an ultimatum Gantz issued in May, demanding that Netanyahu agree to a day-after plan for the Gaza war by June 8. He threatened to quit the coalition if no such agreement was forthcoming, although the prime minister's Likud party and hard-right allies still have a majority of seats without Gantz.
Netanyahu, who has long pegged his reputation on being a security hawk, has faced rising public discontent after the October 7 Hamas attack that happened on his watch. The Israeli offensive on Gaza since then has prompted international criticism, including from Israel's most important ally, the United States.
Gantz joined Netanyahu's government shortly after the October 7 attack. As a member of the war cabinet he has helped manage the Israeli offensive in Gaza, but strains have grown as the war dragged on.
"The seventh of October was a disaster that requires us to go back and get the people's trust, establish a broad and stable unity government to lead us safely through the tremendous challenges in security, in the economy and, most importantly, in the Israeli society," Pnina Tameno, a lawmaker from Gantz's National Unity party, said in a statement.
"Proposing the bill now will allow us to raise it in the current session," she said.
Natanyahu's Likud responded by saying that disbanding the government would hurt the war effort and deal a "fatal blow" to efforts to free over 120 hostages still being held in Gaza since the October 7 raid, in which 1,200 people were killed.
National Unity then issued a second statement blaming Netanyahu for dismantling the government but saying there was still time to find some middle ground.
"Netanyahu, it's not too late to come to your senses - either together we are victorious or you continue alone with the method of 'divide and rule'," it said.
Gantz has emerged as Netanyahu's main political rival since October 7, with recent opinion polls showing he would receive the most votes should a snap election be held.
His party, however, has just eight seats in parliament out of 120 and Netanyahu's original right-wing coalition controls a comfortable majority with 64 seats.Â
