The Russian Foreign Ministry said on Sunday that Syrian President Bashar al-Assad had left office and departed the country after giving orders there be a peaceful handover of power.
In a statement, the ministry did not say where Assad was now and said Russia has not taken part in the talks around his departure.
It said Russia's military bases in Syria had been put on a state of high alert, but that there was no serious threat to them at the current time.
It said Moscow was in touch with all Syrian opposition groups and urged all sides to refrain from violence.
The Syrian opposition announced on Sunday that it had ousted Assad, after seizing control of Damascus on Sunday, ending his family's iron-fisted rule after more than 13 years of civil war in a seismic moment for the Middle East.
Russia, a staunch Assad ally, intervened decisively in 2015 to prop him up during Syria's civil war. But with its military resources mostly tied down in Ukraine, Russia's ability to influence the situation on the ground was far more limited this time round - despite maintaining two military facilities in Syria - and it did not mobilize the same level of resources.
Earlier, deputy chairman of Russia's upper house of parliament Konstantin Kosachyov said on Sunday that the Syrians will have to cope with a full-scale civil war alone, while suggesting that Moscow was ready to support the Syrian people in certain circumstances.
Russian war bloggers have raised fears about the fate of the two Russian military facilities under the opposition but they so far appear to be still functioning while the Russian Embassy in Damascus has said its staff are "fine."
On Friday, the embassy had urged Russian nationals to leave the country.
Kosachyov, a veteran Russian expert in international affairs, predicted that the civil war in Syria would not end with Assad's departure and that tough times were ahead.
"Syria is a very difficult story, for everyone without exception. One way or another, the civil war will not end today, there are too many opposing interests and too many opposing forces. Including outright terrorist groups. And that is why the hardest part is ahead again," Kosachyov wrote on his official Telegram channel.
"It's a tragedy, I repeat, for everyone. And for us Russians, our primary task is to ensure the safety of our compatriots and civilians, including of our diplomats and their families, and, of course, of the military personnel who are there for the sake of Syria, its sovereignty and territorial integrity.
"If the people of Syria continue to need our support, it will be provided. But hardly in the context of a full-scale civil war. The Syrians will have to deal with that themselves," he said.
