Seven sea-going icebreakers, including 1 nuclear-powered ship, would be enough to ensure ice navigation in Russian part of the Gulf of Finland during this winter, given the cargo turnover (175 million tons), the Big Port of St. Petersburg Harbor Master Peter Parinov told reporters. Such calculations have been made by the Central Research Institute of the Navy. In case of severe winters additional icebreakers would be required, Mr. Parinov said. There are now 10 icebreakers operating in the Gulf, including four open water icebreakers, including a nuclear-powered one. Three icebreakers are in a state of readiness. Since the beginning of winter navigation the icebreakers escorted 184 cargo ships to open water, and 23 vessels over the last 24 hours. Currently, two icebreakers are assisting cargo vessels sailing to / from St. Petersburg the Moscow and the Kapitan Sorokin, the ice-powered 50 Years of Victory is ploughing a path to the port of Primorsk, the Kara operates at Ust-Luga and the port icebreaker St. Petersburg escorts ship convoys to / from the ports of Vyborg and Vysotsk.