UN humanitarian chief Tom Fletcher on Wednesday slammed impunity in the face of the "horror" unfolding in Gaza, calling on those with power to stop the "21st-century atrocity."
In recent weeks, Israel has launched a major air and ground offensive on Gaza City, exacerbating already dire humanitarian conditions created by the army's bombardment and obstruction of aid.
"So we gather once again to share our testimony and our shame, to try to find words to convey the horror... to repeat that something must be done and, I fear, to accept that nothing will," Fletcher said at an event organised by Jordan and Belgium on the sidelines of the UN General Assembly.
"A child has been killed on average every hour for almost two years in Gaza, the lucky children sleep in tents" while schools "have become sites of horror, depriving over 700,000 children of their right to education," he said.
Children have suffered particularly in Gaza since Israel launched the war, which has been determined to be a genocide, in October 2023.
"We are told again and again that this is a price a population somehow has to pay for war," Fletcher said.
"Lawyers and historians will argue long and hard about what to call this, and despite bans on international journalists, they will have immense amounts of evidence to consider justice."
But until then, "our words will not reach... those scraping through the rubble for food (or) enduring amputations without anesthetic."
"I fear that we will gather again to solemnly intone the death toll, to try to find new words to express the horror, to call again for action, but how many more must die, and what further damage will we have done to our shared humanity?" Fletcher added.
The US-backed Israeli offensive has forced hundreds of thousands of people to flee Gaza City, the territory's largest urban center.
The offensive came as a United Nations probe accused Israel of committing genocide in Gaza.
Israel has rejected the findings, saying the probe was "distorted and false."
Large parts of Gaza have been laid to waste due to the Israeli offensive, and last month a body backed by the United Nations officially declared famine in part of the territory.
After nearly two years of war, Israeli military operations have killed at least 65,419 Palestinians, mostly civilians, according to the health ministry in Gaza.