Speaking at a news conference on Saturday, Gantz called on the cabinet to agree to a six-point plan laying out a vision for the besieged strip’s governance once the conflict is over.
The Israeli politician, a former defence minister, said that if his demands were not met, he would withdraw his centrist party from the emergency unity government formed last year to oversee the war on Gaza.
Gantz is seen as Netanyahu’s main political rival in Israel. He was a leading figure in the opposition before joining the war cabinet.
His ultimatum deepened the cracks within the Israeli government and added to the mounting pressure against Netanyahu amid increasing domestic and international criticism of his policies in Gaza.
Gantz’s plan calls for releasing Israeli captives in Gaza, demilitarising the territory and forming an international coalition with “American, European, Arab and Palestinian elements” to oversee its civil affairs.
Echoing Netanyahu’s position, Gantz said neither Hamas nor Palestinian Authority President Mahmoud Abbas can rule Gaza after the war.
Demilitarising Gaza would require completely dismantling Hamas’s military wing, which the Israeli military has failed to achieve after 225 days of fighting. The position also matches Netanyahu’s frequent calls for “total victory”.
Still, Gantz took a thinly veiled swipe at the prime minister and his far-right allies. “If you choose the path of fanatics and lead the entire nation to the abyss – we will be forced to quit the government,” he said.
The Israeli offensive in Gaza has killed more than 35,000 people and destroyed much of the besieged enclave. More than 100 Israeli captives remain in the territory.
Talks to reach a captives and ceasefire deal between Israel and Hamas appear to have stalled, with the Netanyahu government rejecting the Palestinian demand to end the war on Gaza.
In a previous agreement – brokered by the United States and Qatar – about 134 captives were released in November; Israel also released dozens of Palestinian prisoners, including children.
Gantz’s request is one of the strongest manifestations of the mounting tension within the war cabinet. In another rare public dispute, Defence Minister Yoav Gallant had also said on Thursday Israel should not be involved in governing Gaza once the fighting ends.
“What we’re seeing more and more of in the past few days is that there is a huge amount of disagreement amongst war cabinet members about the plan going forward for Gaza,” said Al Jazeera correspondent Mohamed Jamjoom.
“And this echoes also the concerns by US government that has said repeatedly that Netanyahu needs to try to figure out a plan for a post-war Gaza scenario,” he added.
Earlier this week, US Secretary of State Antony Blinken chided Israel for the lack of a plan in some of his strongest public criticism.
“One, you have to have a clear, credible plan to protect civilians, which we haven’t seen. Second, we also need to see a plan for what happens after this conflict in Gaza is over, and we still haven’t seen that,” he said.
In addition to opposition within his own government, Netanyahu is also facing growing demonstrations in cities across Israel.
On Saturday, tens of thousands of protesters gathered in Tel Aviv to demand the resignation of the prime minister citing his failure to bring the captives back and his handling of the war.
Israeli opposition leader Yair Lapid also attended the protests on Saturday, pledging to work towards the fall of Netanyahu’s government and the return of Israeli captives. In a social media post, Lapid – a former prime minister himself – later called the current cabinet “the worst government in the country’s history”.
Family members of the captives gathered outside the Israeli military headquarters in Tel Aviv and called on Gantz and Gadi Eisenkot, a former army chief of staff and a current member of Netanyahu’s war cabinet, to replace the prime minister.
“How much more blood will be shed because you lack the courage to do the right thing? It is your duty to expose the truth, it is your moral obligation to swiftly remove Netanyahu from power, because he is abandoning the hostages to their deaths” Hareetz newspaper reported, citing the families at the news conference.
“The only way to rescue all of the hostages is by stopping this war, as part of a signed comprehensive agreement for a hostage release deal,” the group added.