A 24-hour ceasefire came into force in Sudan on Saturday, but with fears it will collapse like previous truces, US and Saudi mediators warned they may break off their efforts to halt the fighting.
The nationwide truce announced by US and Saudi mediators on Friday took effect at 6:00 am local time.
Three hours in, residents in various areas of Khartoum told AFP news agency that shelling and air strikes had halted, at least temporarily.
Multiple truces have been agreed and broken since fighting started in mid-April.
The US placed sanctions on leaders of both the rival factions after the last attempt collapsed at the end of May.
"Should the parties fail to observe the 24-hour ceasefire, facilitators will be compelled to consider adjourning" talks in the Saudi city of Jeddah, which have been suspended since late last month, the mediators said.
Civilians voiced disappointment that the promised ceasefire was so limited in scope.
"A one-day truce is much less than we aspire for," said Khartoum North resident Mahmud Bashir. "We look forward to an end to this damned war."
Sudan specialist Aly Verjee told AFP he saw little reason why this truce should be honoured any more than its predecessors.
"Unfortunately, the incentives have not changed for either party, so it's hard to see that a truce with the same underlying assumptions, especially one of such short duration, will see a substantially different result," said Verjee, a researcher at Sweden's University of Gothenburg.
More than 1,800 people have been killed in the fighting, according to the Armed Conflict Location and Event Data Project.
Nearly two million people have been displaced, including 476,000 who have sought refuge in neighbouring countries, the United Nations says.
The Saudi and US mediators said they "share the frustration of the Sudanese people about the uneven implementation of previous ceasefires".
The army, led by Abdel Fattah al-Burhan, said it has "agreed to the proposal", adding in a statement it "declares its commitment to the ceasefire".
The rival paramilitary Rapid Support Forces, commanded by Burhan's former deputy Mohamed Hamdan Daglo, said: "We affirm our full commitment to the ceasefire."
"If observed, the 24-hour ceasefire will provide an important opportunity... for the parties to undertake confidence-building measures which could permit resumption of the Jeddah talks," the US-Saudi statement said.
The fighting has sidelined efforts to revive Sudan's transition to civilian rule, which was derailed by a 2021 coup by the two generals before they fell out.
It has also complicated the coordination of international efforts to deliver emergency relief to the 25 million civilians that the United Nations estimates are in need.