More than 30 aid trucks entered Gaza on Sunday, the largest convoy to the war-ravaged Palestinian territory since deliveries began trickling in again over a week ago, the UN said.

The United Nations humanitarian organization OCHA said 33 trucks carrying water, food, and medical supplies had gone into Gaza on Sunday, through the Rafah border crossing with Egypt.

"This is the largest delivery of humanitarian aid since 21 October, when limited deliveries resumed," OCHA said in an update on the situation in Gaza sent early Monday.

To date, it said, 117 trucks had entered Gaza through the crossing since limited deliveries resumed to the crowded Palestinian territory of 2.4 million people, which is facing a near-total siege and relentless Israeli bombardment.

Before the siege, some 500 trucks carrying aid and other goods entered Gaza every day.

Israel imposed the siege and unleashed its massive bombing campaign after Hamas gunmen stormed across the border on 7 October, killing 1,400 people, mostly civilians, and seizing 230 hostages, according to Israeli officials.

Israel's strikes have since then killed more than 8,000 people, half of them children, the Hamas-controlled health ministry in the territory said. 

Thousands of buildings have been flattened, with more than half the population displaced.

UN chief Antonio Guterres voiced alarm that Israel was intensifying its military operations in Gaza, warning that "the world is witnessing a humanitarian catastrophe".

A US government official, speaking on condition of anonymity, said Sunday that Israel was committed to allowing 100 aid trucks into Gaza daily — a figure the UN has said was needed to meet the most basic needs.

OCHA welcomed the latest aid deliveries, but stressed that "a much larger volume of aid is needed on a regular basis to prevent further deterioration in the dire humanitarian situation, including civil unrest".

"In particular, entry of fuel to operate medical equipment and water and sanitation facilities is urgently required."

Of the 117 trucks allowed in so far, it said that 70 had carried medical supplies, and 60 of them brought in food and nutritional items.

Only 13 carried water and sanitation supplies, it said.  

And Israel has blocked all deliveries of fuel, saying it would be exploited by Hamas to manufacture weapons and explosives.