Russian President Vladimir Putin has ordered the military to withdraw the "main part" of their forces in Syria, saying they had largely achieved their goals.
He told a meeting at the Kremlin that the pullout would start on Tuesday.
The comments come amid fresh peace talks in Geneva aimed at resolving the Syrian conflict.
Russia is a key ally of Syrian President Bashar al-Assad and the Kremlin said he had been informed.
Its entry into the Syrian civil war tipped the balance in favour of the Syrian government, allowing it to recapture territory from rebels.
Mr Putin also said that Russia's Hmeimim airbase and the its port at Tartus would continue to operate as normal.
He said both must be protected "from land, air and sea".