Turkey says a Russian jet has violated its airspace and it has summoned the Russian ambassador to Ankara.
Turkish President Recep Tayyip Erdogan warned Russia would “face consequences if it continues such violations”.
Tensions have been high between Ankara and Moscow since Turkey shot down a Russian plane which violated its airspace near Syria in November.
Russia has been carrying out air strikes in Syria to support government troops near the Turkish border.
“A Su-34 plane belonging to the Russian Federation air force violated Turkish airspace at 11:46 local time yesterday (Friday),” the Turkish foreign ministry said.
Its statement said the Russian ambassador had been summoned to “strongly protest at and condemn” the incident.
It called the violation a “concrete indication of Russian acts aiming to escalate problems” and warned Russia “will be held responsible for any dire consequences which can emerge from such irresponsible acts”.
Turkey, a vocal opponent of Syria’s President Bashar al-Assad, had long complained of Russian jets violating its airspace along the border with Syria – something Moscow denies.
Ankara was backed by Nato – of which it is a member – when two Turkish F-16s shot down a Russian SU-24 on 24 November.
Turkey said the plane intruded into its airspace and ignored repeated warnings to leave. Russia insisted the jet had never crossed over from Syrian territory and did not receive any warnings.
Nato Secretary General Jens Stoltenberg on Saturday urged Russia “to act responsibility and to fully respect Nato airspace” and “take all necessary measures to ensure that such violations do not happen again”.
Russia has not yet responded to the latest incident but reacted with fury over the downing of its plane in November, introducing a raft of sanctions designed to damage Turkey’s economy.
Moscow’s ban on the import of Turkish foods, the sale of charter holidays for Russians to Turkey and most construction projects with Turkish firms was expected to cost the Turkish economy at least $10bn.