Russian forces entered a besieged Syrian opposition enclave in the southern city of Daraa on Tuesday, witnesses said.
Their presence could dampen a recent confrontation between its defenders and Bashar Al Assad’s forces.
Daraa is near the borders with Jordan and Israel, making it important geopolitically.
Russia has had to balance the goal of restoring the regime of Bashar Al Assad and maintaining stable relations with his country’s neighbours.
Jordan’s King Abdullah met Russian leader Vladimir Putin in Moscow on Monday. They discussed stabilisation prospects in Syria and Arabic-language media said the king raised the subject of Daraa specifically.
“It is the best we could get,” a rebel commander who gave his name as Ahmad said from the city’s Daraa Al Balad district.
“Russian disengagement forces just entered and a proportion of the fighters will leave,” he said.
The commander said that the Russian forces, comprising military police, entered Daraa with the Eighth Brigade, a group composed of former rebel fighters.
Moscow formed it as a proxy unit after most of southern Syria was handed back to the regime in a tacit deal between Russia, the US and Israel in 2018.
At the time, former president Donald Trump had terminated US support for Syrian rebel groups which had included powerful anti-tank weapons.
Syrian opposition sources in Amman confirmed that Russian forces and their Damascus proxies entered Daraa Al Balad on Tuesday.
Assad regime forces and pro-Iranian militia groups have besieged Daraa Al Balad since the end of July, when a three-year de-escalation deal supervised by Russia collapsed.
On Monday, regime forces fired rockets at the enclave from mobile launchers. One man was killed, activists in the area said.
Daraa is the birthplace of the 2011 revolt against five decades of Assad family rule.
When the regime cracked down on peaceful demonstrations, the uprising escalated into civil war.
Last month, King Abdullah told CNN that Jordan had been attacked last year by drones with an “Iranian signature”.
He did not name the area struck, but Jordanian officials have made it clear they are concerned about the spread of Hezbollah-linked militias in Daraa and elsewhere in southern Syria.