Russia's first Borey class ballistic missile nuclear submarine, the Yury Dolgoruky, will be officially put into service with the Russian Navy on Sunday, the designer of the sub said.

"The hoisting of the flag and the signing of the acceptance act will be held at the Sevmash shipyard in Severodvinsk on Sunday, December 30," the Rubin design bureau said in a statement on Saturday.

On the same day, the Sevmash will float out a third Borey class submarine, the Vladimir Monomakh.

A second Borey class vessel, the Alexander Nevsky, is undergoing sea trials and could join Russia's Pacific Fleet in 2014.

The Borey class submarines are expected to form the core of Russia's strategic submarine fleet, replacing the aging Project 941 (NATO Typhoon class) and Project 667 class (Delta-3 and Delta-4) boats. Russia is planning to build eight Borey and Borey-A class subs by 2020.

A Borey class strategic submarine is 170 meters (580 feet) long, has a hull diameter of 13 meters (42 feet), a crew of 107, including 55 officers, a maximum depth of 450 meters (about 1,500 feet) and a submerged speed of about 29 knots.

All the Borey class strategic submarines will carry up to 16 Bulava ballistic missiles with multiple warheads.