President Vladimir Putin has ordered the Russian military to "act in a very tough way" against any threat to its forces in Syria.
Putin told defense officials in Moscow December 11 that Russian forces in Syria should "immediately destroy" such targets.
Last month, the Turkish military downed a Russian bomber on the Syrian border, triggering a bitter row between Moscow and Ankara.
Turkey says the bomber entered its airspace, which Russia denies.
Without naming Turkey, Putin warned against "further provocations."
The Russian president also said the military had provided air cover, weapons, and supplies to the Free Syrian Army, a Western-backed opposition group fighting President Bashar al-Assad.
But Kremlin spokesman Dmitry Peskov later said Russia "supplies weapons to the legitimate authorities" of Syria.
Moscow has been accused of targeting the moderate Syrian opposition, rather than the Islamic State group.
Putin said it was important to develop cooperation "with all states that have a real interest in destroying the terrorists."
Based on reporting by AP, AFP, and BBC