KHARTOUM - Some foreign nationals began evacuating from a Red Sea port in Sudan on Saturday, even as air strikes again rocked the capital Khartoum after a week of fighting between rival commanders that has killed hundreds of civilians across the nation.

The bloody onslaught of urban warfare has trapped large numbers in the Sudanese capital. The airport has been repeatedly targeted and many residents have been unable to leave their homes or get out of the city to safer areas.

The United Nations and foreign states have urged rival military leaders to honour declared ceasefires that have mostly been ignored, and to open safe passage both for fleeing civilians and for the supply of badly needed aid.

With the airport closed and skies unsafe, thousands of foreigners - including embassy staff, aid workers and students in Khartoum and elsewhere in Africa's third largest country - have also been unable to get out.

Saudi Arabia has evacuated Gulf citizens from Port Sudan on the Red Sea, 650 km (400 miles) from Khartoum. Jordan will use the same route for its nationals.

Western countries are expected to send planes for their citizens from Djibouti, though the Sudanese army has said airports in Khartoum and Darfur's biggest city Nyala are problematic and it was not clear when that might be possible.

One foreign diplomat who asked not to be identified said some diplomatic staff in Khartoum were hoping for evacuation by air from Port Sudan in the next two days. The U.S. Embassy warned Americans that it could not assist convoys from Khartoum to Port Sudan and travel would be at individuals' own risk.

The army, under Abdel Fatteh al-Burhan and the rival Rapid Support Forces (RSF), headed by Mohamed Hamdan Dagalo, known as Hemedti, have so far failed to observe ceasefires agreed almost daily since hostilities broke out on April 15.

Saturday's fighting breached what was meant to be a three day truce from Friday to allow citizens to reach safety and visit family during the Muslim holiday of Eid al-Fitr. Both sides accused the other of not respecting the truce.

BOMBARDMENT

Any let-up in fighting on Saturday could accelerate a desperate rush to flee by many Khartoum residents, after days trapped in their homes or local districts under bombardment and with fighters roaming the streets.

Residents of Khartoum and the adjoining sister cities of Omdurman and Bahri reported air strikes near the state broadcaster and battles in areas including near the army headquarters on Saturday.

A resident of Bahri said there had been no water or electricity for a week and frequent air strikes. "We are waiting for the big fight. We are terrified of what's coming," he said.

Live television feeds showed a huge cloud of black smoke rising from Khartoum airport and the sound of shooting and artillery booms.

"These horrible planes are back. I never want to hear another airplane again," said a Khartoum resident, referring to fighter jets aiming strikes at paramilitary positions.

International medical charity Medecins Sans Frontieres (MSF) appealed for safe passage. "We need ports of entry where we can bring specialist trauma staff and medical supplies," said MSF Sudan operations manager Abdalla Hussein.

The Sudanese doctors union said on Saturday that more than two thirds of hospitals in conflict areas were out of service, with 32 forcibly evacuated by soldiers or caught in crossfire.

Beyond Khartoum, the reports of the worst violence have come from Darfur, a western desert region that borders Chad and that suffered warfare from 2003 that has killed as many as 300,000 people and displaced 2.7 million, dragging on after successive peace deals.

A U.N. update on Saturday said looters had taken at least 10 World Food Programme vehicles and six other food trucks after overrunning the agency's offices and warehouses in Nyala, in south Darfur.

SUDDEN COLLAPSE

Sudan's sudden collapse into warfare dashed plans to restore civilian rule, brought an already impoverished country to the brink of humanitarian catastrophe and threatened a wider conflict that could draw in outside powers.

There has been no sign yet that either side in the deadly power struggle can secure a quick victory or is ready to talk. The army has air power but the RSF is widely embedded in urban areas.

However, Burhan said on Saturday that "we all need to sit as Sudanese and find the right way out to return hope and life," his most conciliatory comments since fighting began.

Hemedti's brother, Abdulrahim Hamdan Dagalo, who is second in command of the RSF, said in a video his forces should attack the army "in all venues".

After a 2021 coup, Burhan and Hemedti had held the top two positions on a ruling council that was meant to hand over to civilian rule and merge the RSF into the army.

The World Health Organization reported on Friday that 413 people had been killed and 3,551 injured since fighting broke out. The death toll includes at least five aid workers in a country reliant on food aid.

(Reporting by Khalid Abdelaziz in Khartoum, Nafisa Eltahir, Ahmed Tolba, Hatem Maher and Aidan Lewis in Cairo and Giulia Paravicini in Nairobi Writing by Angus McDowall Editing by Frank Jack Daniel and Frances Kerry)