Explosions and fires rocked Sudan's wartime capital Port Sudan on Tuesday, a witness said, part of a days-long drone assault that has torched the country's biggest fuel depots and damaged its main gateway for humanitarian aid.

Sudan's army-aligned government on Tuesday severed diplomatic ties with the United Arab Emirates, accusing the Gulf state of supplying weapons used by the rival paramilitaries to strike its de facto capital.

Drones struck Port Sudan all day on Tuesday, hitting the main port, the city's power station and the country's last functioning international airport. Witnesses also told AFP they heard explosions from anti-aircraft missiles west of the city, which has also come under repeated attack this week.