In a late-night televised address on Saturday, Netanyahu said while war came with a heavy price, Israel had "no choice but to continue fighting for our very existence, until victory".
Egyptian mediators have been working to restore the ceasefire, which Israel abandoned in March after seeking to extend a temporary truce in which 38 hostages were released.
Hamas, whose militants carried out the October 7, 2023 attack on Israel that triggered the war, has said it would only free the remaining hostages under a deal that ends the war.
Earlier on Saturday, Hamas said that it had recovered the body of a guard killed in an Israeli air strike this week and who was holding Edan Alexander, an Israeli dual national soldier believed to be the last American citizen held alive in Gaza.
The fate of Alexander was unknown, Hamas said. Netanyahu did not mention Alexander in his remarks.
Israel has pounded Gaza with air strikes since the ceasefire collapsed. Palestinian health authorities said at least 50 Palestinians had been killed in strikes on Saturday.
President Donald Trump's envoy Steve Witkoff said in March that freeing Alexander, a 21-year-old New Jersey native who was serving in the Israeli army when he was captured during the October 7, 2023 attacks, was a "top priority".
His release was at the centre of talks held between Hamas leaders and US negotiator Adam Boehler in March.
Hamas had said on Tuesday that it had lost contact with the militants holding Alexander after their location was hit in an Israeli attack.
Fewer than half of the 59 hostages still held in Gaza are believed to remain alive.
Israel put Gaza under a total blockade in March and restarted its assault on March 18 after talks failed to extend the ceasefire. Hamas says it will free remaining hostages only under an agreement that permanently ends the war; Israel says it will agree only to a temporary pause.
Since renewing its attacks, Israel has seized swathes of Gaza and ordered hundreds of thousands of residents to evacuate in what Palestinians fear is a step towards permanently depopulating swathes of land. The Gaza health ministry says 1600 people have been killed in the past month.
Palestinian health officials said the military had escalated its strikes across the Gaza Strip, killing at least 92 people in the past 48 hours, at least 50 of them on Saturday.
On Friday, the Israeli military said it hit about 40 targets across the enclave over the past day. The military on Saturday announced that a 35-year-old soldier had died in combat in Gaza.
Netanyahu spoke after a second indirect meeting between US and Iranian officials where the sides agreed to start drawing up a framework for a potential nuclear deal.
Oman, which is mediating between the countries, stated that discussions aim to reach a binding agreement ensuring Iran is completely free of nuclear weapons and sanctions, while maintaining its ability to develop peaceful nuclear energy.
In his televised address, Netanyahu said he was committed to preventing Iran from obtaining nuclear weapons.
Hamas on Saturday also released an undated and edited video of Israeli hostage Elkana Bohbot. Hamas has released several videos over the course of the war of hostages begging to be released. Israeli officials have dismissed past videos as propaganda.
The war was triggered by Hamas' October 7 attack on southern Israel in 2023, in which 1200 people were killed and 251 taken hostage to Gaza, according to Israeli tallies.
Since then, more than 51,000 Palestinians have been killed in the Israeli offensive, according to local health authorities.
