• The RSF, led by Gen Mohamed Hamdan Dagalo, has claimed to control key sites in the capital, Khartoum.
• Ruto asked IGAD leaders to take a firm position to restore peace in Khartoum.
The Intergovernmental Authority on Development (IGAD) on Sunday called for an immediate cessation of hostilities between the warring parties in Sudan.
President William Samoei Ruto joined Presidents Salva Kiir (South Sudan), Yoweri Museveni (Uganda), Ismail Omar Guelleh (Djibouti) and Hassan Sheikh Mohamud (Somalia) for a virtual meeting of Heads of State to discuss the crisis.
Ruto asked IGAD leaders to take a firm position to restore peace in Khartoum.
The leaders called on the Transitional Sovereign Council General Abdel Fattah al-Burhan and General Mohamed Hamdan Dagalo to stop the war and return to the negotiation.
IGAD resolved to send Presidents Kiir, President Ruto and President Guelleh at the earliest possible time to reconcile the conflicting groups.
They said stability in Sudan is key to the social and economic stability of the region.
The conflict, they added, undermines the peace progress achieved over the last four months.
The leaders also asked the two groups to provide a safe corridor for humanitarian assistance in Khartoum and other affected towns.
The army and a paramilitary are fighting over control of the country which has left more than 100 dead.
Violence between the army and a paramilitary group called the Rapid Support Forces (RSF) continued overnight into its third day on Monday, according to BBC.
Nearly 100 people have been killed, a doctors' union said, and one estimate put the number of injured at 1,100.
Both sides claimed to control key sites in the capital Khartoum, where residents sheltered from explosions.
Earlier on Sunday, they held a temporary ceasefire to allow the wounded to be evacuated, although it was not clear how strictly they stuck to it.
Doctors warned that the situation at hospitals in Khartoum is extremely difficult and that the fighting was stopping both staff and medical supplies from reaching injured people.
The fighting is part of a vicious power struggle within the country's military leadership, which has escalated into violence between rival factions.
The two men at its centre disagree over how the country should transition to civilian rule.
Sudan has been run by generals since a coup overthrew the long-standing authoritarian president, Omar al-Bashir, in 2019.
On Sunday and early Monday, the RSF claimed to occupy sites in the capital Khartoum such as the presidential palace, and the adjoining city of Omdurman, as well as in the western region of Darfur and Merowe Airport in the north of the country.
But some accounts indicated that the army had regained control of the airport, with the military saying they were dealing with "small pockets of rebels".
The army has previously denied that the RSF had seized key sites in the capital, and witnesses in the country said the army appeared to be making gains after blasting RSF bases with air strikes.
The Sudanese army said it had taken hold of RSF bases in Port Sudan, Kasala, Kadaref, Demazin and Kosti.
The RSF claimed to occupy sites in Omdurman and Darfur, as well as Merowe Airport in the north.
But later accounts indicated that the army had regained control of the airport, with the military saying they were dealing with "small pockets of rebels".
Witnesses said the army appeared to be gaining the upper hand in the country's power struggle after blasting RSF bases with air strikes.
Leading Arab states and the US have also urged a resumption of talks aimed at restoring a civilian government, while the African Union has announced that it is sending its top diplomat, Moussa Faki Mahamat, to try to negotiate a ceasefire.
Egypt and South Sudan also offered to mediate between the warring factions, according to a statement by the Egyptian presidency.
Meanwhile, the World Health Organisation says more than 83 people have been killed and more than 1,100 people injured across the country since Thursday. It does not specify how many civilians have died in the fighting.
Among the dead are three staff members of the UN World Food Programme (WFP), which has suspended its operations in the country.
In a statement, the WFP said it was "horrified" by the news of the deaths, adding that one of its aircraft had been damaged at Khartoum International Airport during an exchange of gunfire on Saturday, which it says impacted its ability to provide aid.
Sudan state television is reported to have stopped transmissions, but it was not immediately clear what caused the break in programming.
The RSF, led by Gen Mohamed Hamdan Dagalo, has claimed to control key sites in the capital, Khartoum.
However, that assertion was rejected by Sudan's leader, Gen Abdel Fattah al-Burhan, who heads the country's governing Sovereign Council.
The violence broke out on Saturday after days of tensions over the roadmap for the country's transition to civilian rule. One of the main sticking points is over the plans to incorporate the 100,000-strong RSF into the army and who would then lead the new force. Ends