Israel's destruction of civilian infrastructure in Gaza violates the Geneva Conventions and amounts to a "war crime," the U.N.'s human rights chief said Thursday.

"Extensive destruction of property, not justified by military necessity and carried out unlawfully and wantonly, amounts to a grave breach of the Fourth Geneva Conventions, and a war crime," Volker Turk told reporters.

Turk's comments came a day after Israeli Prime Minister Benjamin Netanyahu ordered troops to prepare to enter Gaza's now-crowded southern city of Rafah, which Israel had previously declared a "safe zone" and ordered Palestinians to flee too.

Last month, the International Court of Justice (ICJ) issued an interim order demanding Israel stop obstructing aid deliveries into Gaza and improve the humanitarian situation in the enclave, following a lawsuit by South Africa accusing Tel Aviv of committing genocide.

Israel has pounded Gaza since a cross-border attack by Palestinian group Hamas in October, which Tel Aviv said killed nearly 1,200 people.

At least 27,840 Palestinians have since been killed and 67,317 others injured in the Israeli onslaught, according to local health authorities.

About 85% of Gazans have been displaced by the Israeli offensive, while all of them are food insecure, according to the U.N. Hundreds of thousands of people are living without shelter, and ⁠less than half of aid trucks are entering the territory than before the start of the conflict.