“There is a repeated displacement, constant fear and witnessing family members literally dismembered before their eyes,” he said. “These psychological injuries have led children as young as 5 to tell us that they would prefer to die.”

Lockyear slammed the United States, saying he was appalled it had repeatedly used its veto power to block the council from demanding an immediate humanitarian ceasefire in the Israeli war on Gaza.

“The people of Gaza need a ceasefire, not when practicable, but now,” Lockyear said. “They need a sustained ceasefire, not a temporary period of calm. Anything short of this is gross negligence.”

The U.S. has vetoed three U.N. Security Council resolutions since the start of the current fighting on Oct. 7, most recently blocking on Tuesday a demand for an immediate humanitarian ceasefire as it instead pushes the council to call for a temporary ceasefire linked to the release of hostages held by Hamas.

China’s U.N. Ambassador Zhang Jun told the council he felt “appalled” by Lockyear’s briefing.

“We hope the tragic picture that he painted of Gaza for us can touch the conscience of a certain member of this council,” Zhang said.

The United States had said it was concerned that the draft resolution it vetoed on Tuesday could jeopardize talks between the U.S., Egypt, Israel and Qatar that seek to broker a six week pause in the war and the release of hostages.

Deputy U.S. Ambassador to the U.N. Robert Wood did not acknowledge Lockyear’s briefing. He said the U.S. was pushing Israel to allow more aid into Gaza and had told its ally it should not proceed with a ground offensive in Rafah in southern Gaza “in the absence of a viable plan to protect civilians.”

“We all want to see a durable end to this conflict,” Wood said. “The pace of hostage talks can be frustrating… council support for this diplomacy is critical to increase pressure on Hamas to accept the agreement on the table.”

Britain’s U.N. Ambassador Barbara Woodward described Lockyear’s briefing as “harrowing.” Britain abstained on Tuesday’s vote, while the remaining 13 council members voted in favor of the Algerian-drafted resolution.

Slovenia’s U.N. Ambassador to the Security Council Samuel Zbogar asked, “What kind of a council have we become if we remain untouched by the tearful briefing that we heard today by the secretary general of Médecins Sans Frontières?”

The war began when fighters from the Hamas militant group that runs Gaza attacked Israel on Oct. 7, killing 1,200 people and capturing 253 hostages, according to Israeli tallies. In retaliation, Israel launched a military invasion on Gaza that health authorities say has killed nearly 30,000 Palestinians with thousands more bodies feared lost amid the ruins, more than 70,000 wounded and more than 1.5 million homeless.

“Today our staff are back at work risking their lives once again for their patients. What are you willing to risk?” Lockyear asked the council.