By El Tayeb Siddig and Nafisa Eltahir
KHARTOUM (Reuters) -The United Nations warned on Monday that the conflict in Sudan could force 800,000 people to flee the country as battles between rival military factions persisted in the capital despite a supposed ceasefire.
Hundreds of people have been killed and thousands wounded over 16 days of battles since disputes between the Sudanese army and the paramilitary Rapid Support Forces (RSF) erupted into conflict on April 15.
The crisis has unleashed a humanitarian disaster, damaged swathes of Khartoum, risked drawing in regional powers and reignited conflict in the Darfur region.
Many fear for their lives in the power struggle between the army chief and RSF head, who shared control of the government after a 2021 coup but fell out over a planned transition to civilian rule.
Both sides agreed on Sunday to extend a much-violated truce by 72 hours, and the U.N. told Reuters the rival forces may hold ceasefire talks in Saudi Arabia. But air strikes and artillery rang out on Monday as smoke hung over Khartoum and neighbouring cities.
U.N. official Raouf Mazou said the body's refugee agency was planning for an exodus of 815,000 people including 580,000 Sudanese as well as foreign refugees now living in the country. The country's population numbers 46 million.
Some 73,000 have already left Sudan, he said.
Egypt reported 40,000 Sudanese had crossed its border, and those who made the journey said conditions were arduous. Others have gone to Chad, South Sudan and Ethiopia, or sailed across the Red Sea to Saudi Arabia on evacuation boats.
At least 528 people have been killed and 4,599 wounded, the health ministry said. The United Nations has reported a similar number of dead but believes the real toll is much higher.
Foreign governments pulled out their citizens over the past week in air, sea and land operations, though several countries ended efforts. The U.S. government said on Monday that its convoys from Khartoum to the Red Sea harbour of Port Sudan evacuated more than 700 people over the weekend.
Britain said it was exploring ways to provide humanitarian assistance to Sudan along with its international allies, the United Nations and aid organisations after evacuating nearly 2,200 people.
Meanwhile, those Sudanese who stayed behind faced hardship and danger.
"I show up to work for two or three hours then I close up because it's not safe," said Abdelbagi, a barber in Khartoum who said he had to keep working because prices were rising.
People who ventured onto the streets on Monday were shocked by the transformation.
"We saw dead bodies. The industrial area that was all looted. We saw people carrying TVs on their backs and big sacks looted from factories," said resident Mohamed Ezzeldin.
Power and water supplies are uncertain, there is little food or fuel, most hospitals and clinics are out of service and soaring transport costs are making it ever harder to leave.
The U.N. and other aid organisations have cut services, though the World Food Programme said it was resuming operations in more secure areas on Monday after staff were killed early in the war.
"The scale and speed of what is unfolding in Sudan is unprecedented," said Martin Griffiths, a senior U.N. official for humanitarian and emergency relief who will visit Sudan on Tuesday.
Victoria, one of the tea sellers who used to dot Khartoum's streets before the fighting began, said her children are struggling to understand what is happening.
"So I risk my life to try to work and if God helps me, I'll get them some food, and if he doesn't I'll keep trying. But just sitting useless doesn't help and being scared doesn't help," she said.
Jamila, a woman still in Khartoum with her family, is only eating one meal a day because so little food is available. RSF troops are stationed in front of their house and refuse to leave. "The sound of fighting is in our ears all day," she said.
Both sides said on Monday they were making progress without commenting directly on the ceasefire violations.
The army said it had cut RSF's combat effectiveness by half and stopped it trying to reinforce its positions in the capital. The RSF said it still controls main locations of Khartoum and was itself beating back army reinforcements.
Reuters could not verify either side's claims.
(Aditional reporting by Emma Farge and Gabrielle Tetrault-Farber in Geneva and Michelle Nichols in New York; Writing by Michael Georgy, Angus McDowall and Cynthia Osterman; Editing by Michael Perry, Philippa Fletcher, Angus MacSwan and Sonali Paul)