The incident came as several countries including the United States, Saudi Arabia and neighbouring Egypt voiced alarm at the worsening hunger situation in war-torn Sudan, calling for pauses in fighting to let in more aid.

Three of the 16 trucks in the convoy -- which was carrying life-saving food assistance for vulnerable communities in Alsayah village -- were damaged and caught fire, said the WFP's Gift Watanasathorn, adding that all members of the convoy were "safe and accounted for".

"Humanitarian staff and assets must never be a target," Watanasathorn said, urging the warring parties to "respect international humanitarian law".

The spokesperson did not specify who was behind the assault, which took place in an area controlled by the paramilitary Rapid Support Forces (RSF), at war with the regular army since April 2023.

Mellit, about 65 kilometres northeast of North Darfur's besieged capital of El-Fasher, has been under paramilitary control since April 2024.

El-Fasher remains the last major stronghold under army control in the western Darfur region, and has been under paramilitary siege for over a year.

In a statement, the RSF blamed the Sudanese army for carrying out the attack by air, calling it a "treacherous act of aggression".

There was no immediate comment from the army.

- Humanitarian 'deterioration' -

Both sides in the conflict have been accused of using starvation as a weapon of war, as well as obstructing or looting humanitarian aid.

In a similar attack in June, five aid workers were killed in a joint WFP-UNICEF convoy en route to El-Fasher.

On Wednesday, several key players in the diplomacy surrounding the Sudan crisis -- including the United States, Egypt, Saudi Arabia, Switzerland, the African Union and the United Nations -- issued a joint statement calling for urgent pauses in fighting to allow aid to reach civilians.

They said they were "appalled by the continuous deterioration of the humanitarian situation in Sudan", citing severe malnutrition and famine, as well as widespread restrictions on humanitarian access.

Also joining the statement was the United Arab Emirates, which has been accused of backing the RSF, most recently by hiring Colombian mercenaries to fight against the army on the paramilitaries' behalf.

Paramilitary attacks in North Darfur have intensified in recent months as the RSF seeks to consolidate its hold on all of Darfur after losing Sudan's capital Khartoum in March.

The wider war -- now in its third year -- has plunged Sudan into one of the world's worst humanitarian crises, with more than a million people on the brink of starvation in North Darfur alone.

While famine was officially declared last year in three displacement camps around El-Fasher, the UN had warned it could spread to the city itself -- though a lack of access and reliable data has prevented an updated assessment.

The fighting has killed tens of thousands, displaced millions and created a dire hunger crisis.