United Nations High Commissioner for Human Rights Volker Turk blamed Israel for the soaring death toll in the territory, where it launched a fierce assault in response to unprecedented attacks by Hamas militants in October.

The health ministry in Hamas-run Gaza said on Thursday that the death toll from the conflict had reached at least 40,005 people, with another 92,401 wounded - most of them women and children.

"Today marks a grim milestone for the world," Turk said in a statement.

"Most of the dead are women and children. This unimaginable situation is overwhelmingly due to recurring failures by the Israeli Defense Forces to comply with the rules of war," he added.

"The scale of the Israeli military's destruction of homes, hospitals, schools and places of worship is deeply shocking."

He said his office had documented "serious violations" of international humanitarian law by both the Israeli military and Palestinian armed groups, including Hamas.

He reiterated a call for an immediate ceasefire and for the release of Israeli hostages held in Gaza and of Palestinians "arbitrarily detained".

Ceasefire talks resumed in Qatar on Thursday.