“The unfolding catastrophe makes the need for a humanitarian ceasefire more urgent with every passing hour.

“The parties to the conflict – and, indeed, the international community – face an immediate and fundamental responsibility: to stop this inhuman collective suffering and dramatically expand humanitarian aid to Gaza,” Guterres said.

Guterres was formally launching a recently announced US$1.2 billion UN humanitarian appeal to help 2.7 million Palestinians over the entire Gaza Strip and parts of the West Bank and East Jerusalem.

Aid trucks have been crossing into Gaza from Egypt through the Rafah crossing, but the level remains well below the level before October 7, with Israel saying it needs time for security checks of vehicles, and they are not bringing fuel.

“Without fuel, newborn babies in incubators and patients on life support will die,” Guterres said.

“The way forward is clear. A humanitarian ceasefire – now. All parties respecting all their obligations under international humanitarian law,” he said.

03:05

Humanitarian crisis unfolding in Gaza as food supplies run out after total Israeli blockade

Humanitarian crisis unfolding in Gaza as food supplies run out after total Israeli blockade

Militants from Palestinian group Hamas stormed into Israel on October 7, killing some 1,400 people, mostly civilians, including through targeting homes and revellers at a music festival.

According to the Hamas-run health ministry in Gaza, 10,222 people have died including more than 4,000 children in the Gaza Strip since Israel launched its strikes in retaliation.

Guterres also deplored the killings of media workers. According to the New York-based Committee to Protect Journalists, at least 36 journalists and media workers have been killed.

“More journalists have reportedly been killed over a four-week period than in any conflict in at least three decades,” Guterres said.

Guterres again voiced alarm about the “clear violations of international humanitarian law that we are witnessing.”

“Let me be clear: No party to an armed conflict is above international humanitarian law,” he said.

Guterres did not name Israel. He outraged Israel on October 24 at a Security Council meeting where he alleged violations of humanitarian law and said that the Hamas attacks “did not occur in a vacuum,” leading Israeli officials to accuse the UN chief of justifying violence.

Guterres denied that was his intention and on Monday repeated his condemnation of “the abhorrent acts of terror perpetrated by Hamas,” and urged the Islamist militants to free hostages taken on October 7.

Eighty-eight UN relief workers have been killed so far, UN agency chiefs said on Monday.

“For almost a month, the world has been watching the unfolding situation in Israel and the Occupied Palestinian Territory in shock and horror at the spiralling numbers of lives lost and torn apart,” the heads of 18 UN organisations including Unicef and the World Health Organization said in a rare joint statement late on Sunday.

“Scores of aid workers have been killed since October 7 including 88 UNRWA colleagues – the highest number of United Nations fatalities ever recorded in a single conflict,” they said, referring to the UN relief and works agency for Palestinian refugees.

During the last heavy conflict in Gaza between Israel and Hamas, in 2014, 11 UNRWA staff were killed, according to the United Nations.

The UNRWA currently employs some 13,000 staff in the Gaza Strip, a territory that is home to 2.4 million people.

The agency chiefs expressed revulsion at the toll on both sides since the October 7 cross-border attack by Hamas Palestinian militants from Gaza into Israel, which left about 1,400 people dead, mainly civilians, Israeli authorities say.

Additional reporting by Agence France-Presse