The United Nations chief warned at a high-level UN meeting on Tuesday that the situation in the Middle East is growing more dire by the hour with the risk of the Gaza war spreading through the region increasing as societies splinter and tensions threaten to boil over.
Secretary-General Antonio Guterres called for an immediate humanitarian cease-fire to deliver desperately needed food, water, medicine and fuel.
He appealed "to all to pull back from the brink before the violence claims even more lives and spreads even farther."
Guterres told the UN Security Council's monthly meeting on the decades-old Israeli-Palestinian conflict – which has turned into a major event with ministers from the war's key parties and a dozen other countries flying to New York – that the rules of war must be obeyed.
The secretary-general said the grievances of the Palestinian people cannot justify "the horrifying and unprecedented October 7 acts of terror" by Hamas in Israel and demanded the immediate release of all hostages.
But Guterres also stressed that "those appalling attacks cannot justify the collective punishment of the Palestinian people."
He expressed deep concern at "the clear violations of international humanitarian law," calling Israel's constant bombardment of Gaza and the level of destruction and civilian casualties "alarming."
Protecting civilians "is paramount in any armed conflict," he said.
Without naming Hamas, the UN chief stressed that "protecting civilians can never mean using them as human shields."
Guterres also criticised Israel without naming it, saying "protecting civilians does not mean ordering more than one million people to evacuate to the south, where there is no shelter, no food, no water, no medicine and no fuel, and then continuing to bomb the south itself."
The United States is pushing for adoption of a resolution that would condemn the Hamas attacks in Israel and violence against civilians, and reaffirm Israel's right to self-defence.
There were some expectations that it might be voted on Tuesday, but diplomats said it is still being negotiated.
A draft obtained on Monday by The Associated Press would also demand the immediate release of all hostages, strongly urge respect for international laws on conducting war and protecting civilians, call on all countries to take steps to prevent a spillover, and demand immediate humanitarian access to Gaza.
Meanwhile, the UN health agency on Tuesday also called for an immediate humanitarian cease-fire in Gaza to be able to distribute fuel and essential, life-saving health supplies, including to major hospitals in the strip's northern half.
"For people in the Gaza Strip, the situation is desperate. It will become catastrophic without the safe and continuous passage of fuel and health supplies, and additional humanitarian assistance," the World Health Organisation said in a statement.
The organisation said some health facilities in northern Gaza, including the territory's largest Shifa hospital, were waiting for WHO's supplies and fuel.
Among them is the Indonesian hospital, which suffered a brief power outage and was forced to shutter some critical services due to lack of fuel.
Hospitals will be 'mass graves' as Gaza crisis worsens: doctor
Gaza's only oncology hospital, the Turkish Friendship Hospital, remains partially functional, putting around 2000 cancer patients at risk, the agency added.
Supported by UN agency for Palestinian refugees, the health agency said it delivered 34000 litres of fuel on Monday to four major hospitals in southern Gaza and the Palestine Red Crescent.
Such an amount was only enough to keep ambulances and critical hospital functions running for a little over 24 hours.
It also distributed medicine and other supplies to key hospitals in southern Gaza, as well as the Palestine Red Crescent.