US Vice President Kamala Harris urged an immediate ceasefire in Gaza, upping the pressure on key ally Israel as heavy fighting raged in the Palestinian territory.

Harris's comments on Sunday, the most forceful to date by a US administration official, came as Washington led a push to lock in a truce before Ramadan, the Muslim fasting month that begins in around one week.

Envoys from the United States, Qatar and Hamas were in Cairo for the latest round of talks over a proposal to pause the five-month-old war.

According to a senior US official, Israel has broadly accepted the terms, which would see stepped-up aid deliveries and the exchange of hostages for Palestinian prisoners.

Several sticking points reportedly remain, including Hamas's insistence that Israeli forces entirely withdraw from the devastated territory.

"Hamas claims it wants a ceasefire. Well, there is a deal on the table," Harris said.

Taking an unusually sharp tone, she demanded Israel "do more to significantly increase the flow of aid" into Gaza, where she said people are starving and the conditions "inhumane".

"Given the immense scale of suffering in Gaza, there must be an immediate ceasefire."

Pressure for a truce has mounted after attempted aid deliveries have descended into scenes of tragedy, and convoys have failed to reach families gripped by food shortages in the north.

After UN warnings of famine in Gaza, the United States started airdropping food rations on Saturday, following in the steps of Jordan and some other countries.

"It is imperative that we expand the flow of aid into Gaza to alleviate the dire humanitarian situation," US Secretary of State Antony Blinken wrote on social media platform X on Sunday.

- 'Only civilians' -

Harris and Blinken are both due to meet with Israeli war cabinet member Benny Gantz in Washington on Monday.

The former Israeli military chief, a centrist and longtime rival of Netanyahu, will also meet White House national security advisor Jake Sullivan.

A White House official said the discussions would include the need for a hostage deal, temporary ceasefire and expanding aid flows into Gaza.

Despite the latest push to halt the fighting sparked by Hamas's October 7 attack on Israel, there has been no letup to the pummelling of Gaza.

Late Sunday, an AFP correspondent reported several air strikes in southern Gaza's Rafah and Khan Yunis.

Earlier in the day, two of the latest victims, twin babies Naeem and Wissam Abu Anza, were buried as their mother Rania wept in agony.

A relative, Shehda Abu Anza, said "only civilians" were in the house when it was bombed, killing 14 members of one family.

"All of them were sleeping when suddenly a missile hit and destroyed the whole house," he told AFP as residents searched the rubble with their bare hands -- for bodies but also to salvage scarce food.

The infants were among 30,410 fatalities, most of them women and children, reported by the Hamas-run territory's health ministry since Israel launched military operations to eliminate Hamas last October.

The war began after the Palestinian militant group's unprecedented October 7 attack on southern Israel that resulted in the deaths of around 1,160 people, according to an AFP tally of official figures.

Around 250 people were taken hostage, according to Israeli figures. The Israeli army says 130 hostages remain in Gaza, of whom 31 are believed to be dead.

- Aid truck hit? -

Palestinian families have told AFP of grinding up animal feed and foraged plants to have something to eat, while the health ministry said at least 16 children died of malnutrition in recent days in Gaza's aid-deprived north.

Witnesses told AFP that an Israeli strike hit an aid truck in central Gaza's Deir al-Balah on Sunday, killing several people.

"We did not know what to do, whether to run away or to rescue the people in the truck. Then they hit it with the second missile," said witness Reyad al-Quraan.

Contacted about the incident, the Israeli military told AFP: "It was not an aid truck that was struck," but did not elaborate.

On Thursday, more than 100 people were killed in chaotic scenes around a convoy of aid trucks in Gaza City.

Gaza health officials said Israeli forces opened fire into the crowd, causing a "massacre", while Israel's army said most victims were trampled or hit by trucks in a crush for food.

Numerous world leaders have called for a probe.

The UN Security Council  has voiced concern over Gaza's "alarming levels of acute food insecurity", and urged "the immediate, rapid, safe, sustained and unhindered delivery of humanitarian assistance at scale".

During Sunday prayers, Pope Francis called for a ceasefire and for Gazan civilians to be given "safe access to urgently needed humanitarian aid".

- Truce talks -

A Hamas official said that the group wants the ceasefire deal to include "the entry of at least 400 to 500 trucks per day" carrying food, medicine and fuel.

Osama Hamdan, a Lebanon-based Hamas official, told Qatar's Al-Araby TV that the group insisted on a complete, rather than "temporary", ceasefire and on "ending the aggression against our people".

Israeli Prime Minister Benjamin Netanyahu has so far rejected pulling troops out of Gaza before Hamas is destroyed and all hostages are freed.

Netanyahu has faced mounting calls to secure the release of the hostages, from their desperate families and from a resurgent anti-government protest movement.

Israel, which has so far announced no plans to join the Egypt talks, has demanded Hamas provide it with a list of all 130 remaining captives, including more than 30 who are feared dead.