The United Nations has said the prospect of a full Israeli incursion into the cramped Gaza town of Rafah was "terrifying" and risked an "extremely high" number of casualties.
UN human rights chief Volker Turk on Monday urged world powers to "restrain rather than enable" as fears of a looming ground incursion grew among more than one million Palestinians trapped in the territory's far south.
"A potential full-fledged military incursion into Rafah - where some 1.5 million Palestinians are packed against the Egyptian border with nowhere further to flee - is terrifying, given the prospect that an extremely high number of civilians, again mostly children and women, will likely be killed and injured," Turk said in a statement.
"Sadly, given the carnage wrought so far in Gaza it is wholly imaginable what would lie ahead in Rafah."
Beyond the pain and suffering of the bombs and bullets, this incursion into Rafah may also mean the end of the meagre humanitarian aid that has been entering and distributed with huge implications for all of Gaza, he said, including the hundreds of thousands at grave risk of starvation and famine in the north, he added.
"My office has repeatedly warned against actions that violate the laws of war. The prospect of such an operation into Rafah, as circumstances stand, risks further atrocity crimes," said Turk.
'Those with influence must restrain rather than enable'
He said those who defy international law had been put on notice and accountability must follow.
"The world must not allow this to happen," Turk said.
"Those with influence must restrain rather than enable. There must be an immediate ceasefire. All remaining hostages must be released. And there must be renewed collective resolve to reach a political solution."
Bombing after promising to be safe
Israeli Prime Minister Benjamin Netanyahu has vowed to send ground troops into the crowded Rafah area as part of his goal of eliminating Hamas.
His declarations have sparked international alarm.
Tel Aviv forced over 1.4M Palestinians to relocate to the small city of Rafah, promising them that the city on Egypt's border would be safe.
Israel's relentless offensive in Gaza has killed at least 28,340 people, mostly women and children since October 7, the health ministry says.