Negotiations for the release of the captives held in Gaza have been ongoing, with the latest talks taking place in the Qatari capital Doha, where US President Donald Trump was visiting on Wednesday.
Netanyahu's office said the premier had discussed with Witkoff and his negotiating team captives and missing persons.
Witkoff later said Trump had "a really productive conversation" with the Qatari emir about a Gaza deal, adding that "we are moving along and we have a good plan together".
Fighting meanwhile raged in Gaza, where civil defence official Mohammed al-Mughayyir told AFP 80 people had been killed by Israeli bombardment since dawn, including 59 in the north.
AFP footage from the aftermath of a strike in Jabalia, northern Gaza, showed mounds of rubble and twisted metal from collapsed buildings. Palestinians, including young children, picked through the debris in search of belongings.
Footage of mourners in northern Gaza showed women in tears as they kneeled next to bodies wrapped in bloodstained white shrouds.
"It's a nine-month-old baby. What did he do?" one of them cried out.
Hasan Moqbel, a Palestinian who lost relatives, told AFP: "There are no homes fit for living. I have no shelter, no food, no water. Those who don't die from air strikes die from hunger, and those who don't die from hunger die from lack of medicine."
Israel's military on Wednesday urged residents in part of a Gaza City neighbourhood to evacuate, warning that its forces would "attack the area with intense force".
'Unjustifiable'
From the occupied West Bank, Palestinian president Mahmud Abbas said Wednesday he favoured a "ceasefire at any price" in Gaza, accusing Netanyahu of wanting to continue the war "for his own reasons".
Mohammad Awad, an emergency doctor in northern Gaza's Indonesian Hospital, told AFP that supply shortages meant his department could not properly handle the flow of wounded from the Jabalia strike.
"There are not enough beds, no medicine, and no means for surgical or medical treatment, which leaves doctors unable to save many of the injured who are dying due to lack of care", he said.
Awad added that "the bodies of the martyrs are lying on the ground in the hospital corridors after the morgue reached full capacity. The situation is catastrophic in every sense of the word."
Israel imposed an aid blockade on the Gaza Strip on March 2 after talks to prolong a January 19 ceasefire broke down.
The resulting shortages of food and medicine have aggravated an already dire situation in the Palestinian territory, although Israel has dismissed UN warnings that a potential famine looms.
UN Secretary General Antonio Guterres on Wednesday called for "an immediate cessation of hostilities," in Gaza.
Italian Prime Minister Giorgia Meloni said the humanitarian situation in Gaza was "ever more dramatic and unjustifiable".
A US-led initiative for aid distribution under Israeli military security drew international criticism as it appears to sideline the United Nations and existing aid organisations, and would overhaul current humanitarian structures in Gaza.
'Full force'
Medical charity Medecins Sans Frontieres said the plan would make "aid conditional on forced displacement" and vetting of the population.
It added in a statement that Israel was creating "conditions for the eradication of Palestinian lives in Gaza".
Israel resumed major operations across Gaza on March 18, with officials later talking of retaining a long-term presence in the Palestinian territory.
Following a short pause in air strikes during the release of US-Israeli captive Edan Alexander on Monday, Israel resumed its pounding of Gaza.
Netanyahu said on Monday that the military would enter Gaza "with full force" in the coming days.
He added that his government was working to find countries willing to take in Gaza's population.
The Israeli government approved plans to expand the offensive earlier this month, and spoke of the "conquest" of Gaza.
Israel's genocidal war on Gaza has killed at least 52,928 people in Gaza, mostly women and children.
*This story was edited by Ahram Online
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