Russian forces have established a presence in the Kurdish enclave of Efrin in northern Syria, on the border with Turkey, a spokesman for the main Kurdish militia told dpa on Monday.
Redur Xelil, a spokesman for the People's Protection Units (YPG), said the Russians would provide training in "modern warfare" to the Kurdish militia.
"Our forces have proven their effectiveness in the fight against terrorism," Xelil said, adding that the military presence would also establish a "direct point of contact" with the Russians.
There was no Russian confirmation of the information.
The YPG is the main component of the Syrian Democratic Forces (SDF), which is the primary ally of the United States on the ground fighting against Islamic State in the east of the country.
SDF forces are currently working to encircle al-Raqqa, Islamic State's de-facto capital in the country.
Efrin is disconnected from the bulk of the territory held by the Kurds in Syria.