MOSCOW, June 29. /TASS/. Russia’s Stary Oskol submarine, the third boat in Project 636.3 series for the Black Sea Fleet, on a voyage to its permanent base has passed the Bosporus and Dardanelles straits, the Black Sea Fleet spokesman Vyacheslav Trukhachev told reporters on Wednesday.

"The newest diesel-powered Stary Oskol submarine that successfully passed the state test program and that in June 2015 entered service with the Russian Navy, on a voyage to its permanent base from the Northern to the Black Sea Fleet has passed the Bosporus and Dardanelles straits and entered the Black Sea," Trukhachev said.

The Russian Black Sea Fleet currently operates four Project 636.3 submarines. The fleet is to receive a total of six submarines of this project.

The Russian Navy received the lead submarine Novorossiysk in August 2014 and the second Project 636.3 submarine Rostov-on-Don on December 30, 2014. In late 2015, the submarine Rostov-on-Don launched Kalibr cruise missiles from the Mediterranean Sea to destroy facilities of the Islamic State terrorist organization in Syria. The third Project 636.3 submarine Stary Oskol joined the Russian Navy in 2015. The fourth submarine Krasnodar was delivered to the Navy on November 5, 2015. All these submarines were built at the Admiralty Wharves Shipyard. The fifth and the sixth submarines are planned to be delivered to Russia’s Black Sea Fleet later this year. In addition, a series of six similar submarines will be built for Russia’s Pacific Fleet.