The Russian Navy maintains a fleet of about 60 nuclear-powered and diesel-electric submarines, a senior Navy official said on Thursday.
"These 60 vessels include 10 nuclear-powered strategic submarines, over 30 nuclear-powered attack submarines, diesel-electric submarines and special-purpose subs," the source said.
Delta-IV and Delta-III class subs form the backbone of Russia's strategic submarine fleet. They each carry 16 ballistic missiles with multiple warheads, and feature advanced electronics and noise reduction.
"The world's largest Typhoon-class submarines also remain in service with the Russian Navy," the official said.
The Dmitry Donskoy submarine has been modernized as a test platform for Russia's new Bulava missile. Two other subs, the Arkhangelsk and the Severstal, remain in reserve at a naval base in Severodvinsk in north Russia.
"They will most likely be modernized to carry new-generation sea-based cruise missiles to match the U.S. Ohio class submarines," he said.
Russia has started mooring trials of the first Borey class nuclear-powered strategic submarine, which will be equipped with Bulava sea-based ballistic missiles.
The Yury Dolgoruky submarine, built at the Sevmash plant in northern Russia, was taken out of dry dock in April 2007.
The vessel is 170 meters (580 feet) long, has a hull diameter of 13 meters (42 feet), a crew of 107, including 55 officers, maximum depth of 450 meters (about 1,500 feet) and a submerged speed of about 29 knots. It can carry up to 16 ballistic missiles and torpedoes.
Two other Borey class nuclear submarines, the Alexander Nevsky and the Vladimir Monomakh, are currently under construction at the Sevmash shipyard and are expected to be completed in 2009 and 2011. Russia is planning to build a total of eight submarines of this class by 2015.
Russia's nuclear-powered attack submarine fleet comprises vessels of the Oscar II and Akula class. Each sub is equipped with 24 SS-N-19 Shipwreck long-range anti-ship cruise missiles.
A fourth-generation Graney class nuclear-powered attack submarine will be delivered to the Russian Navy in 2010-2011. The Severodvinsk submarine combines the ability to launch a variety of long-range cruise missiles (up to 3,100 miles) with nuclear warheads, and effectively engage hostile submarines and surface warships.
"The tests of the cruise missile for the submarine are under way," the source said.
Diesel-electric submarines in the Russian Navy are represented by Kilo class vessels. They will be gradually replaced by Project 667 Lada class submarines. The sub features a new anti-sonar coating for its hull, an extended cruising range, and advanced anti-ship and anti-submarine weaponry, including Club-S cruise missile systems.
The first submarine of the Lada class, named the St. Petersburg, is undergoing sea trials and may enter service with the Russian Navy this year.
A second Lada class submarine, the Kronshtadt, which is the first in the production series, is also being built at St. Petersburg's Admiralty Shipyards and will be commissioned in 2009.
A third submarine, whose keel was laid in November 2006, is named after a city associated with Russian naval glory - Sevastopol - and is expected to be launched in 2010.
The source also said the Russian Navy has several 'special purpose' submarines designed for testing of new technologies and weaponry. Some open sources earlier reported the existence of Project 20120 B-90 Sarov diesel-electric submarine, which has a nuclear reactor as a supplementary power generator.
The vessel was commissioned in 2007 and according to some reports may be used by Russia's Northern Fleet as a spy vessel in northern waters.