MOSCOW, May 30. /ITAR-TASS/. A new generation diesel-electric submarine Friday left St. Petersburg's Admiralty shipyard for Baltic Sea trials.

The near-complete diesel-electric Novorossiysk will be at sea for less than a month and will return to base for final fitting ahead of joining the Black Sea naval fleet, a defence industry source told Itar-Tass on Friday. Three-month mooring trials have already been completed.

Novorossiysk is the first in a series of 636.6 Varshavyanka Project vessels, Black Sea Fleet Commander Admiral Viktor Chirkov told ITAR-TASS.

Six submarines of this class are planned for Black Sea duty and are aimed at building up the potential of Russia's naval task force in the Mediterranean.

St. Petersburg's Rubin design bureau has created an ultra-quiet, high combat capability vessel with a surface speed of 20 knots (37 kph), maximum submerged depth of around 300 meters and subsea displacement of around 4,000 tonnes. Its 52-man crew can remain at sea for 45 days.

Novorossiysk's keel was laid in August 2010. The project’s second submarine, named Rostov-on-Don, was laid in November 2011, the third, Stary Oskol, in August 2012 and the fourth, Krasnodar, in February 2014.