THE United Nations has said those in northern Gaza face "diminishing conditions for survival" after "virtually no aid" has been delivered in 40 days.

The theft in Gaza over the weekend of nearly 100 trucks loaded with food and other humanitarian aid sent prices soaring and caused shortages in central Gaza, where most of the population of 2.3 million people have fled and where hundreds of thousands are crammed into squalid tent camps.

Experts say famine may already have set in in the north, where Israel has been waging a weekslong offensive that has killed hundreds of people and driven tens of thousands from their homes.

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Even after the military gave permission for a delivery to the northernmost part of Gaza, virtually cut off from food for more than a month by an Israeli siege, the United Nations said it could not deliver most of it because of turmoil and restrictions from Israeli troops on the ground.

UN spokesperson Stéphane Dujarric told reporters in New York: "This is happening when the IPC Famine Review Committee said just 11 days ago that parts of northern Gaza face an imminent risk of famine - and that immediate action is needed in days, not weeks.

"The result is that bakeries and kitchens in North Gaza governorate have shut down, nutrition support [for children and pregnant and breastfeeding women] has been suspended, and the refuelling of water and sanitation facilities has been completely blocked."

Between 100,000 and 130,000 others have been displaced to Gaza City, where the UN has said essential resources like shelter, water and healthcare are severely limited.

A shortage in flour and the closure of a main bakery in central Gaza have exacerbated the dire humanitarian situation as Palestinian families struggle to obtain enough food.

Almost all of Gaza’s roughly 2.3 million people now rely on international aid for survival, and doctors and aid groups say malnutrition is rampant. Food security experts say famine may already be underway in hard-hit north Gaza.

Aid groups accuse the Israeli military of hindering and even blocking shipments in Gaza.

A crowd of people waited dejectedly in the cold outside the shuttered Zadna Bakery in Deir al-Balah on Monday.

Among them was Umm Shadi, a displaced woman from Gaza City, who told The Associated Press there was no bread left due to the lack of flour — a bag of which costs as much as 400 Israeli shekels (£84) in the market, she said, if any can be found.

“Who can buy a bag of flour for 400 shekels?” she asked.

Nora Muhanna, another woman displaced from Gaza City, said she was leaving empty-handed after waiting five or six hours for a bag of bread for her kids.

“From the beginning, there are no goods, and even if they are available, there is no money,” she said.

Meanwhile, dozens lined up in Deir al-Balah to get their share of lentil soup and some bread at a makeshift charity kitchen.

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Refat Abed, a displaced man from Gaza City, no longer knows how he can afford food.

“Where can I get money?” he asked. “Do I beg? If it were not for God and charity, my children and I would go hungry,”

Meanwhile, in the south, hundreds of truckloads of aid are sitting on the Gaza side of the border because the UN says it cannot reach them to distribute, again because of the threat of lawlessness, theft and Israeli military restrictions.

Israel’s offensive has killed almost 44,000 Palestinians, more than half of them women and children, according to local health authorities, who do not distinguish between civilians and combatants in their toll.

The war has left much of the territory in ruins and forced around 90% of Gaza’s population of 2.3 million to flee, often multiple times.