Sudan's paramilitary Rapid Support Forces [RSF] has agreed to a 72-hour ceasefire on humanitarian grounds from 6 am [local time].
"The truce coincides with the blessed Eid al Fitr ... to open humanitarian corridors to evacuate citizens and give them the opportunity to greet their families," the RSF said in a statement on Friday.
There was no immediate comment from the Sudanese army on the latest ceasefire announce by RSF.
At least 350 people have been killed in the power struggle between two previously allied leaders of the ruling military junta, army chief Burhan and RSF leader General Mohamed Hamdan Dagalo.
The conflict has dashed hopes for progress towards democracy in Sudan.
Thousands of civilians streamed out of Khartoum as gunfire and explosions sounded on Thursday.
The UN estimated that 10,000-20,000 people have also crossed into Chad to flee fighting in the western region of Darfur.
A doctors' group said at least 26 people were killed and 33 were injured in El-Obeid, a city west of Khartoum, on Thursday. Witnesses there described clashes between the army and RSF troops and widespread looting.
UN chief Antonio Guterres, speaking to reporters after meeting virtually with the heads of the African Union, the Arab League and other organizations on Thursday, said: "There was a strong consensus on condemning ongoing fighting in Sudan and calling for cessation of hostilities as an immediate priority".
Urging a three-day ceasefire, he said civilians trapped in conflict zones should be allowed to escape and to seek medical treatment, food and other supplies.
He said a ceasefire to mark Eid al Fitr must be ''an immediate priority.'' The United States endorsed the ceasefire proposal.
Army chief al Burhan had told Al Jazeera that he would support a truce on condition it allowed citizens to move freely - something he said the RSF had prevented. He also said he saw no partner for negotiations, and "no other option but the military solution".
His rival, Dagalo, widely known as Hemedti, told Al Jazeera he was ready to implement a three-day truce.
"We are talking about a humanitarian truce, we are talking about safe passages ... we are not talking about sitting down with a criminal," Dagalo said, referring to Burhan.
Burhan accused Dagalo, until last week his deputy on the council that has ruled since a coup two years ago, of "a power grab".
An alliance between the two men had mostly held since the overthrow of strongman Bashir, whose rule saw Sudan become an international pariah that was on the U.S. terrorism list.
The latest violence was triggered by disagreement over an internationally backed plan to form a new civilian government. Both sides accuse the other of thwarting the transition.
On Thursday, Sudan's military chief refused to hold talks with his opponent but said he was open for mediation.
Sudan's army chief General Abdel Fattah al Burhan and RSF commander Hamdan Dagalo had received separate phone calls from Turkish President Erdogan, Saudi and Qatari foreign ministers, Egyptian intelligence chief and the US, calling for a temporary ceasefire.
Previous ceasefire agreements were largely ignored by parties to the conflict which started on Saturday.
