Regime forces and Kurdish fighters agreed to a truce in the flashpoint Syrian city of Hasakeh on Sunday after two days of Russian mediation efforts, a military source told AFP.
The northeastern city has been rocked by deadly clashes between US-backed Kurdish forces and fighters loyal to President Bashar al-Assad since Wednesday.
In a bid to calm tensions, a delegation of Russian officials from the coastal Hmeimim military airport arrived in the nearby city of Qamishli on Saturday for talks with the two sides.
By Sunday, the Russian-mediated negotiations reached an agreement, a Syrian military source told AFP.
It included a "halt to all hostilities and the return to regime forces of any positions seized by Kurdish fighters" since Wednesday, the source said.
Casualties would also be transferred north to Qamishli, and additional negotiations would take place on Monday.
"A delegation of Russian officials and members of the (pro-regime militia) National Defence Forces (NDF) have arrived at Qamishli airport for a meeting tomorrow (Monday)," a source from the Hasakeh governorate said.
A local journalist working with AFP toured seven army checkpoints that had been seized by Kurdish fighters and confirmed that regime forces were back in control.
But Kurdish fighters still held three positions previously controlled by the NDF in Al-Nashwa, a southern district of Hasakeh, the journalist said.
The regime and Kurdish forces share a common enemy in the Islamic State (IS) jihadist group, but there have been growing tensions between them in Hasakeh.
Clashes broke out last week after Kurds demanded the NDF be dismantled in Hasakeh, and violence escalated Thursday when regime warplanes began bombarding Kurdish-held positions in the city for the first time.
Regime aircraft flew over the city on Sunday morning but without carrying out further raids, said the Syrian Observatory for Human Rights.
The unprecedented strikes prompted the US-led coalition to scramble aircraft to protect its special operations forces helping the Kurdish People's Protection Units (YPG) as they battle IS in northern Syria.
Since Wednesday, the fighting had left 43 people dead including 27 civilians, among them 11 children, according to the Britain-based Observatory.
Thousands of civilians have fled the city, where electricity has been cut and bakeries shut.
In the northern province of Aleppo, the scene of heavy clashes all month between government forces and rebels allied with jihadists, 28 civilians were among 38 people killed Saturday in strikes by the regime and its Russian allies, the Observatory said.
More than 290,000 people have been killed since Syria's conflict erupted in March 2011, and millions have been forced to flee their homes.