The US top diplomat called on Hamas on Tuesday to accept a plan for an "immediate ceasefire" with Israel as mediators met for a third day in Cairo in efforts to end almost five months of fighting.

As famine threatens Gazans, US and Jordanian planes again airdropped food aid into the besieged territory of 2.4 million people in a joint operation with Egypt and France.

Bombing and fighting in the war sparked by the October 7 attack killed another 97 people, said the health ministry in the Hamas-run territory, where Israel said its jets had struck 50 targets over the past day.

In Cairo, US and Hamas envoys were meeting Egyptian and Qatari mediators for a third day in protracted negotiations to end the fighting and free hostages before the Muslim fasting month of Ramadan starts on March 10 or 11.

Egypt's AlQahera News, which is close to the country's intelligence services, said the "negotiations are difficult but they are continuing", citing an unnamed senior official.

The parties in Egypt -- so far excluding Israel -- have discussed a plan for a six-week truce, the exchange of dozens of hostages for hundreds of Palestinian prisoners, and increased aid into Gaza.

US Secretary of State Antony Blinken on called on Hamas to accept the plan to pause the fighting and allow in more desperately needed humanitarian aid.

"We have an opportunity for an immediate ceasefire that can bring hostages home, that can dramatically increase the amount of humanitarian assistance getting to Palestinians who so desperately need it, and then also set the conditions for an enduring resolution," Blinken said.

"It is on Hamas to make decisions about whether it is prepared to engage in that ceasefire," the US top diplomat added as he met the Qatari prime minister in Washington.

As conditions in Gaza deteriorate and the spectre of famine looms, Israel has also faced increasingly sharp rebukes from Washington.

Vice President Kamala Harris expressed "deep concern about the humanitarian conditions in Gaza" during talks on Monday with war cabinet member Benny Gantz, a centrist political rival of right-wing Prime Minister Benjamin Netanyahu.

- 'We want to eat and live' -

American cargo planes airdropped more than 36,000 meals into Gaza Tuesday in a joint operation with Jordan, which said French and Egyptian planes also took part.

The United Nations has warned famine is "almost inevitable" in the Palestinian territory.

Israeli media reported, meanwhile, that the country's negotiating team had so far boycotted the Cairo talks after Hamas had failed to provide it with a list of the living hostages.

Israel has said it believes 130 of the original 250 captives remain in Gaza, but that 31 have been killed.

Senior Hamas leader Bassem Naim on Monday said that the group did not know "who among them are alive or dead, killed because of strikes or hunger", and that the captives were being held by "numerous groups in multiple places".

He said that, in order for all of them to be located, "a ceasefire is necessary". Speaking on Tuesday, Naim said a truce and hostage release deal "could happen within days". But he added that, "if the Americans are serious about it, they have to put enough pressure" on Netanyahu and his government.

The war started with Hamas's October 7 attack on southern Israel that resulted in about 1,160 deaths, most of them civilians, according to a tally based on Israeli official figures.

Israel's retaliatory offensive has killed 30,631 people, mostly women and children, according to the health ministry.

Fighting raged on in Gaza, with Hamas official reporting dozens of Israeli air strikes near the European Hospital in Hamad, near the main southern city of Khan Yunis.

Khan Yunis residents said decomposing bodies were lying in streets lined with destroyed homes and shops.

"We want to eat and live," said Nader Abu Shanab, pointing to the rubble with blackened hands.

"Take a look at our homes. How am I to blame, a single, unarmed person without any income in this impoverished country?"

- Israel-UN tensions -

The UN World Health Organization said an aid mission to two hospitals in northern Gaza had found children dying of starvation.

"The lack of food resulted in the deaths of 10 children," said WHO chief Tedros Adhanom Ghebreyesus.

On Tuesday, the WHO estimated at least 8,000 Gaza patients needed evacuating for treatment, which would relieve pressure on the few functioning hospitals.

Tensions between Israel and the United Nations flared on Monday, with Israel recalling its ambassador over the handling of allegations of sexual assault during the October attack.

Israel accused the UN of taking too long to respond to the claims, as the world body published a report that said there were "reasonable grounds to believe" rapes were committed and that hostages taken to Gaza had also faced sexual violence.

"In most of these incidents, victims first subjected to rape were then killed, and at least two incidents relate to the rape of women's corpses," the report said.

Shortly before the report's release, Israel said it was recalling its ambassador Gilad Erdan over what it said was an attempt by the UN to "silence" reports of sexual violence by Hamas.

UN chief Antonio Guterres's spokesman denied trying to suppress the report. The war has sparked violence across the region, including near-daily exchanges of fire between Israeli forces and Lebanon's Hezbollah movement.

US envoy Amos Hochstein, who urged a diplomatic solution during a Beirut visit Monday, met with Israeli Defence Minister Yoav Gallant in Tel Aviv.

Gallant told Hochstein that Israel was committed to the diplomatic process but "emphasised that Hezbollah's aggression is dragging the parties to a dangerous escalation", his office said.