Benny Gantz, who leads the party Strength for Israel, is leaving the government, he announced in a televised speech according to several media.
He says the decision was “complex” and “painful”, according to Sky News.
Gantz has since last month threatened to resign if Netanyahu does not approve a post-war plan by June 8.
In his ultimatum, Gantz had, among other things, demanded that everyone be brought home from the hostages, but also that an international government should be created for a demilitarized Gaza after the war.
Netanyahu’s coalition government is sandwiched between centrists such as Gantz and the far right, who also hold ministerial posts and have issued their own ultimatums not to split the government.