After more than two years of war between the Sudanese army and the paramilitary Rapid Support Forces, needs have reached overwhelming levels, Bertrand said.

"We are forced to choose who we save and who we don't," Bertrand said after returning from a three-week mission to assess aid logistics.

"It is an inhumane dilemma that humanitarian actors have to face and it goes completely against our values."

Bertrand said teams were prioritising children, pregnant women and breastfeeding mothers "in the hope that others can hold on".

The conflict in Sudan, which began in April 2023, has killed tens of thousands and displaced nearly 12 million, creating what the UN describes as the world's largest displacement and hunger crisis.

Conditions in Darfur have deteriorated sharply since the RSF seized the North Darfur capital of El-Fasher, the army's last stronghold in the region, on October 26.

The UN-backed Integrated Food Security Phase Classification Initiative (IPC) confirmed this month El-Fasher is facing famine, which has raged in its surrounding displacement camps for over a year.

Aid groups like Bertrand's are scrambling to meet immense needs, with no functional infrastructure.

None of Darfur's airports can receive aid, roads are often impassable and the only access point into the region -- through neighbouring Chad -- is riddled with "administrative obstacles", in addition to exorbitant costs and insufficient international funding.

- 'Total collapse' -

"It's the entire supply of an area the size of France, with 11 million inhabitants, moving partly on the backs of donkeys," he said, describing a "state of anarchy", the total collapse of government structures, rampant banditry and security threats on the roads, including "extortion, theft, assaults and arrests".

In Tawila -- a refuge town now sheltering more than 650,000 people fleeing El-Fasher and the nearby Zamzam camp, both now under RSF control -- Bertrand said he encountered people who "have absolutely nothing left", while aid organisations are unable to meet demand.

He said the partial suspension of US aid had resulted in a loss of "70 percent of aid" to Darfur, leaving barely "a quarter of needs" covered.

Bertrand also described "80,000 people stranded" along Darfur's roads, many of them subjected to violence, extortion or ransom demands.

Those who reach Tawila often show signs of malnutrition, injuries from torture and gunshot wounds, he said.

He said Darfur now reflects the reality of a country in a state of "decay", accusing the international community of allowing armed groups to "kill each other".

"In another era," he said, "there would have been a United Nations resolution sending a peacekeeping force".