China described the war in Gaza as a "disgrace to civilisation" and called on Thursday for an immediate ceasefire as the conflict stretched into its sixth month despite efforts by mediators to reach a truce.

US President Joe Biden has 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.

However, mediators in Egypt have struggled to overcome tough obstacles in their attempts to negotiate a pause, while the United Nations has warned that famine looms for Palestinians trapped by the fighting.

"It is a tragedy for humankind and a disgrace for civilisation that today, in the 21st century, this humanitarian disaster cannot be stopped," Chinese Foreign Minister Wang Yi told a news conference in Beijing.

China, historically sympathetic to the Palestinian cause, has been calling for a ceasefire since the war began when Hamas militants attacked Israel on October 7.

"The international community must act urgently, making an immediate ceasefire and the cessation of hostilities an overriding priority, and ensuring humanitarian relief an urgent moral responsibility," Wang said.

The war has reduced vast stretches of Gaza to a wasteland of gutted buildings and rubble and sparked a humanitarian disaster for its 2.4 million people.

- 'Catastrophic' hunger levels -

The health ministry in Hamas-run Gaza said Wednesday that 20 people have died of malnutrition and dehydration, at least half of them children.

Only limited aid has reached Gaza's north, where the UN's World Food Programme has warned that hunger has reached "catastrophic levels" in northern Gaza, where aid has been limited.

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

According to Gaza's health ministry, one of the latest victims was a 15-year-old girl who died at Gaza City's Al-Shifa Hospital.

Health ministry spokesman Ashraf al-Qudra said "the famine in northern Gaza has reached lethal levels" and could claim thousands of lives unless Gaza receives more aid and medical supplies.

Gazans were waiting to collect bags of flour outside a UN refugee agency office in the southern city of Rafah, now home to nearly 1.5 million Palestinians, most of them displaced by the war.

"The flour they provide is not enough," said displaced man Muhammad Abu Odeh. "They do not provide us with sugar or anything else except flour."

In Khan Yunis, southern Gaza's largest city, dozens of people went to inspect their homes and take what belongings they could recover after Israeli forces pulled out of the city centre, an AFP correspondent said.

The army has yet to respond to an AFP request to confirm such a withdrawal.

- Ramadan tensions -

The war began after Hamas launched the October 7 attack on southern Israel that resulted in about 1,160 deaths, most of them civilians, according to an AFP tally based on official Israeli 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 Gaza health ministry.

Israeli Prime Minister Benjamin Netanyahu has vowed to push on with the campaign to destroy Hamas, before or after any truce deal.

Biden called on Hamas on Tuesday to accept a 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", see the "release of sick, wounded, elderly and women hostages" and allow for "a surge of humanitarian assistance", the White House said.

One known sticking point centres on an Israeli demand for Hamas to provide a list of hostages still being held, a task Hamas says it is unable to complete while Israeli bombing continues.

The Palestinian Islamist group said in a statement it had "shown the required flexibility with the aim of reaching an agreement", insisting on a complete halt to the fighting.

Violence has flared in past years 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 urged restrictions.

Israel has said Muslims will initially be allowed into the site "in similar numbers" as in recent years, followed by a weekly "situation assessment".

- 'Widespread starvation' -

Jordanian, US and other planes have repeatedly airdropped food into Gaza but WFP deputy chief Carl Skau said "airdrops are a last resort and will not avert famine".

South Africa petitioned the International Court of Justice on Wednesday to impose more emergency measures against Israel over what it described as "widespread starvation" in Gaza.

British Foreign Minister David Cameron also pressed Israel on Wednesday to increase the flow of aid into Gaza.

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

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

Israel, which has recalled its UN envoy in a sign of growing tensions, said the UN Security Council should "designate Hamas immediately as a terrorist organisation" and impose sanctions on it.