A cease-fire in Sudan that was supposed to come into force on Thursday has already been broken, with airstrikes and heavy shelling reported near the presidential palace in the capital Khartoum in the morning.

Artillery fire was also heard in the neighboring town of Omdurman, according to eyewitness reports on Twitter.

The weeklong cease-fire agreed to by both factions in the Sudanese conflict was supposed to be in effect from Thursday until May 11. However, chances that it would hold had been considered slim. 

Deadly combat broke out on April 15 between Sudan's de facto leader Abdel Fattah Burhan, who commands the regular army, and his deputy turned rival Mohamed Hamdan Daglo, who heads the paramilitary Rapid Support Forces (RSF).

The RSF on Thursday accused the military of breaking the terms of the latest cease-fire. It accused the army of bombing RSF positions as well as residential areas in a statement.

The army denied these claims and said RSF fighters had launched an attack on soldiers early on Thursday morning.

Since fighting began in Sudan, cease-fires of up to 72 hours have been repeatedly negotiated only to be repeatedly broken.

Hundreds of people have been killed in the violence so far, with estimates ranging from 500 to 700.

Here are other key headlines about the crisis in Sudan for Thursday, May 4:

UN expects 860,000 refugees from Sudan

The UN refugee agency UNHCR expects 860,000 refugees to flee from Sudan. It is estimated that around 580,000 Sudanese will leaving the country and that an additional 235,000 refugees previously hosted in Sudan will return to their home countries despite adverse conditions. 

Another 45,000 non-Sudanese refugees are expected to leave Sudan for another country of refuge. Most arrivals are expected in Egypt and South Sudan.

According to a joint aid plan by humanitarian organizations presented to international donors in Geneva, $445 million (€402 million) will be needed to support them over the next six months. Emergency measures are planned in Chad, South Sudan, Egypt, Ethiopia and the Central African Republic.

According to the UNHCR, the conflict has currently displaced more than 330,000 people within Sudan and more than 100,000 have fled abroad.

Refugee situation on South Sudan's border is becoming difficult — UNHCR

Marie-Helene Verney, UNHCR representative in South Sudan, the key destination for people fleeing fighting in Sudan, told DW that the situation at the border between the countries is becoming difficult.

According to Verney, the refugees started arriving to South Sudan two weeks ago. "The first week was quiet because people were stuck in Khartoum and really could not leave Khartoum because the fighting was too hard," she said.

In the past two weeks, UNHCR recorded 33,000 people coming through one particular border crossing point, Verney said. However, she is sure that the real numbers are likely to be much higher, as Sudan and South Sudan has a very "long and porous border." 

The situation in this particular location in north-eastern South Sudan, where these 33,000 people arrived, is becoming difficult, Verney said, as this location is particularly remote. "There is almost no infrastructure. Everything has to be airlifted or put on boats," she said.

Verney also mentioned that South Sudan is heavily dependent on Sudan for food, for basic goods, as well as for oil transit. "So there's also a huge economic impact on South Sudan that is likely to play out in the next few weeks and months," Verney said.

UK ends Sudan evacuations after extracting over 2,450 people

The UK said it had ended its evacuation efforts from Sudan after extracting more than 2,450 people on dozens of flights during an eight-day operation.

The foreign office said the last of 30 flights in that period departed late Wednesday from the eastern city of Port Sudan, "concluding the longest and largest evacuation of any Western nation." 

It added that most of those airlifted out of the war-torn east African country were British citizens and their dependents.

More than 1,200 people from other nations, including the US, Ireland, Netherlands, Canada, Germany and Australia, were also taken out.

Biden says Sudan conflict 'must end,' threatens sanctions

US President Joe Biden said the weekslong fighting in Sudan "must end" and authorized potential new sanctions against those responsible for the bloodshed.

"The violence taking place in Sudan is a tragedy — and it is a betrayal of the Sudanese people's clear demand for civilian government and a transition to democracy," he said in a statement.

The US expects the fighting between two military chiefs in Sudan will not likely let up as neither has any incentive to seek peace, Director of National Intelligence Avril Haines said earlier.

UN admits failure to avert war as aid looted

The United Nations has urged warring factions in Sudan to open a humanitarian corridor for aid to be transported, after reports that food supplies were looted in parts of the country.

Martin Griffiths, UN chief for humanitarian affairs, said on Wednesday that six trucks belonging to the World Food Program were looted in Sudan's western region of Darfur, despite assurances of safety and security.

UN deputy spokesperson Farhan Haq said in 17,000 metric tons of food had been looted in places including the capital, Khartoum, and Darfur out of a total 80,00 metric tons of food aid that the agency has in Sudan.

"It's not as if we're asking for the moon," Griffiths said in an online briefing. "We're asking for the movement of humanitarian supplies and people. We do this in every other country, even without cease-fires."

He has called for face-to-face meetings with Sudan's army leader Abdel Fattah al-Burhan and Mohamed Hamdan Dagalo, commonly known as Hemedti, who heads the Rapid Support Forces (RSF) paramilitary.

Even before the conflict broke out, a third of Sudan's 45 million people relied on humanitarian assistance, the UN said.

UN Secretary-General Antonio Guterres said on Wednesday that the organization "was taken by surprise" by the conflict.

"To the extent that we and many others were not expecting this to happen, we can say we failed to avoid it to happen," Guterres told reporters in Kenya.

"A country like Sudan, that has suffered so much... cannot afford a struggle for power between two people."

Hundreds of Nigerians evacuated

More than 430 Nigerian nationals have been evacuated to Nigeria's capital Abuja late on Wednesday after days of logistical delays left them stranded at the Sudan-Egypt border.

Many returnees arrived at the airport in Abuja looking fatigued and with few personal belongings.

"They have gone through a very traumatizing period, but we are glad no life was lost," said Sadiya Umar Farouq, Nigeria's Minister of Humanitarian Affairs.

She said some 2,000 Nigerians remain in Sudan, and more will be evacuated in the coming days.

dh, rm, zc/rs (AFP, Reuters, AP)