"The request for the necessity to close the Bosphorus Strait for the passage of Russian warships under Article 19 of the Montreux Convention was not sent to Turkey," the news agency reported referring to the response of the service.
It was added that the document provides no other details.
As it was reported, Lefortovo court extended arrest of the last four Ukrainian sailors for three months. Earlier, detention was prolonged for the rest POWs captured near Kerch Strait in November 2018.
On November 25, the coast guard ships of the Russian Navy attacked the ships of the Ukrainian Navy, which have been carrying out a scheduled transition from Odesa port to Mariupol port in the Sea of Azov.
21 Ukrainian sailors have been delivered to Lefortovo remand center in Moscow, three others are in the hospital of Matrosskaya Tishina prison, also in the Russian capital. On December 3, the Russian prosecutors officially accused Ukrainian sailors with the 'illegal crossing of the state border' during the attack in the Kerch Strait.