MOSCOW (TASS) — Russian President Vladimir Putin has held a telephone conversation with Turkish President Recep Tayyip Erdogan to discuss the situation in the Black Sea region in the wake of the Kerch Strait incident, the Kremlin’s press-service said.

On November 25, three Ukrainian naval ships violated the rules of navigation through Russia’s territorial waters on the way from the Black Sea to the Sea of Azov. Weapons were used to make them stop in the Kerch Strait. Three Ukrainian military servicemen were lightly wounded. The ships were detained and taken to Kerch. Criminal proceedings were launched in Russia over the violation of the state border. Russia described the incident as a provocation. The Ukrainian authorities initiated the introduction of a state of emergency. The European Union and NATO called for de-escalation of tensions.

The two leaders have discussed the situation in Syria, particularly in Idlib, during the telephone call. “It has been agreed to beef up joint efforts aimed at the implementation of a memorandum on stabilization of the situation in Idlib, signed in Sochi on September 17, including the fight against terror groups”, according to the statement.

According to the Russian-Turkish memorandum signed in Sochi on September 17 after talks between the Russian and Turkish presidents, a demilitarized zone of a depth of 15-20 kilometers should have been created in Idlib by October 15. However, Turkey asked to postpone joint patrolling in Idlib due to its inability to guarantee security on its side.