"I fail to see how such an operation could be consistent with the binding provisional measures issued by the International Court of Justice," Volker Turk told the UN Human Rights Council.

On January 26, the ICJ in The Hague -- while it refrained from ordering an immediate halt to the war in Gaza -- said Israel must do everything to "prevent the commission of all acts within the scope" of the Genocide Convention.

The UN's top court said Israel must facilitate "urgently needed" humanitarian aid to the Palestinian territory, which has been under relentless bombardment and siege since October 7.

"The prospect of an Israeli ground assault on Rafah would take the nightmare being inflicted on people in Gaza into a new dimension," said Turk.

Israeli Prime Minister Benjamin Netanyahu said on Sunday the Israeli army would launch a ground invasion of Rafah in the southern Gaza Strip -- where an estimated 1.4 million Palestinian civilians have sought refuge from the war.

Turk was presenting the latest report from his office in the Palestinian territories.

He repeated that the Hamas attacks on Israel in October were "shocking, profoundly traumatising and totally unjustifiable".

"The killing of civilians, reports of torture and sexual violence inflicted by Hamas and other Palestinian armed groups, and the holding of hostages since that time, are appalling and entirely wrong," he said.

"And so is the brutality of the Israeli response," he added, calling it "carnage".