Envoys pushed on with efforts for a Gaza truce and hostage release deal in Cairo talks Wednesday, hoping to halt nearly five months of fighting before the start of Ramadan next week.

US President Joe Biden had urged Hamas to accept a ceasefire plan with Israel before the Muslim fasting month begins, which could be as early as Sunday, depending on the sighting of the crescent moon.

As negotiators in Egypt sought to overcome tough stumbling blocks, deadly fighting again rocked Gaza where the UN warns famine looms and desperate crowds have stopped and looted food aid trucks.

Dire shortages of food and water amid the devastating Gaza war sparked by Hamas's October 7 attack have killed at least 18 people, said medics in the Hamas-controlled Palestinian territory.

Biden on Tuesday called on the Palestinian Islamist militant group to accept the truce plan brokered by US, Qatari and Egyptian mediators, saying "it's in the hands of Hamas right now".

The proposed deal would pause fighting for "at least six weeks", according to a White House statement on talks between US National Security Advisor Jake Sullivan and the Qatari prime minister.

It would also see the "release of sick, wounded, elderly and women hostages" and allow for "a surge of humanitarian assistance", they said in a Washington meeting on Tuesday.

One known sticking point centres on an Israeli demand for Hamas to hand it a list of the about 100 hostages believed to still be alive -- a task Hamas says it can't complete while bombing continues.

The group said in a statement that it had "shown the required flexibility with the aim of reaching an agreement requiring a comprehensive cessation of aggression against our people".

Biden stressed that "there's got to be a ceasefire because Ramadan -- if we get into circumstances where this continues to Ramadan, Israel and Jerusalem could be very, very dangerous".

- Stumbling blocks -

In past years, violence has flared during Ramadan in annexed east Jerusalem's Al-Aqsa mosque compound -- Islam's third-holiest site and Judaism's most sacred, known to Jews as the Temple Mount.

Hamas has urged Muslims to flock there in great numbers, as they do every year, while some Israeli far-right politicians have argued they should be banned this year.

Israel's government said on Tuesday that Muslim worshippers would initially be allowed to the site "in similar numbers" as in recent years, but that this would be followed by a weekly "situation assessment in terms of security and safety".

The Gaza war broke out after Hamas launched their attack on southern Israel that resulted in about 1,160 deaths, most of them civilians, according to an AFP tally based on Israeli official figures.

The militants also took around 250 hostages. Israel believes 99 of them remain alive in Gaza and that 31 have died.

Israel's retaliatory offensive has killed at least 30,717 people, mostly women and children, according to the health ministry in the Hamas-ruled territory.

Israeli Prime Minister Benjamin Netanyahu has vowed to push on with the campaign to destroy Hamas, before or after any truce deal, while Hamas has demanded a permanent stop to fighting.

In the latest combat, the army said that "a number of terrorists were identified and eliminated, including in a helicopter strike" in the southern city of Khan Yunis.

"AK-47 rifles and ammunition were among the large quantity of weapons located and seized during searches."

- Food trucks looted -

While the war has reduced vast stretches of Gaza to a wasteland of bombed-out buildings and rubble, the siege has sparked a humanitarian disaster for its 2.4 million people.

Hunger has reached "catastrophic levels" in the north, the UN World Food Programme has warned.

"Children are dying of hunger-related diseases and suffering severe levels of malnutrition," it said.

Gaza's health ministry reported that a 15-year-old girl became the latest child to die from malnutrition or dehydration, at Shifa Hospital in Gaza City.

More than 100 people were reported killed in bloody chaos last week when thousands swarmed aid trucks in Gaza. Gaza officials blamed Israel gunfire, while the army insisted most were trampled to death or run over.

Another truck convoy was diverted by Israeli troops within Gaza late Tuesday and then stopped by "a large crowd of desperate people who looted the food", said the WFP.

Jordanian, US and other planes have repeatedly airdropped food into Gaza.

But WFP deputy chief Carl Skau said that "airdrops are a last resort and will not avert famine".

Washington has stepped up pressure on Israel to alleviate the suffering, a message echoed by British Foreign Secretary David Cameron.

"People are dying of hunger. People are dying of otherwise preventable disease," Cameron told the House of Lords ahead of talks with visiting Israeli war cabinet member Benny Gantz.

Cameron said that, as Israel is "the occupying power... it is responsible and that has consequences, including in how we look at whether Israel is compliant with international humanitarian law".

Looking ahead at a post-war future, he also pointed at "the unstoppable momentum we need to see towards a two-state solution".

Anger over Israel's Gaza campaign has grown across the Middle East, stoking violence involving Iran-backed groups in Lebanon, Iraq, Syria and Yemen.

Yemen's Huthi rebels have attacked passing ship traffic in the Red Sea and Gulf of Aden, in what they call a solidarity campaign with Gaza, sparking US and British retaliatory strikes.

The Huthis days ago sank a cargo ship carrying fertiliser which, environmental groups have warned, threatens an ecological disaster.

The US military said Tuesday it shot down three Huthi drones and a missile fired towards one of its destroyers in the Red Sea.