The United Nations has said the prospect of a full Israeli incursion into the crammed Gaza town of Rafah is “terrifying” and risks an “extremely high” number of casualties.

UN human rights chief Volker Turk 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, including the hundreds of thousands at grave risk of starvation and famine in the north.”