ROME, Italy - Three United Nations agencies called Monday on Israel to allow access to the port of Ashdod, north of Gaza, for the urgent delivery of humanitarian aid.

Bringing food and supplies to the besieged population of Gaza, which is increasingly at risk of famine, also depends on the opening of new entry routes into the territory, the World Food Programme (WFP), UNICEF and the World Health Organisation (WHO) said in a joint statement.

The use of Ashdod, located some 40 km (25 miles) north of the Gaza border, is "critically needed by aid agencies", they said, while calling for a "fundamental step change in the flow of humanitarian aid into Gaza".

Allowing humanitarian agencies to use that port "would enable significantly larger quantities of aid to be shipped in and then trucked directly to the badly affected northern regions of Gaza, which few convoys have managed to reach", they said.

The Israel-Hamas war, now in its 100th day, has sparked a humanitarian catastrophe for Gaza's 2.4 million people, who are struggling to get food, water, fuel and medical care.

Opening the Ashdod port would reduce the time it takes to transport food to Gazans from the north, WFP's regional director for the Middle East, Corinne Fleischer, told AFP earlier this month.

"We buy most of our food in Turkey, just bring it to Ashdod port, and then that reduces the lead time," Fleischer said.

"We need border crossings in the north to open, so we can more regularly access the north, where the food security crisis is even deeper," she said.

In December, Israel approved the temporary delivery of aid into Gaza via its southern Kerem Shalom border crossing, opening a new route for supplies after weeks of pressure.