Russia will modernize its fleet of the third-generation Project 971 (Akula class) nuclear-powered attack submarines, Vladimir Dorofeyev, head of the Malakhit Design Bureau, said.

“The Defense Ministry has decided to overhaul all third-generation attack submarines,” Dorofeyev said on Tuesday in an interview with RIA Novosti, the news agency reported.

“The first Project 971 submarine is already being upgraded at the Zvezdochka shipyard [in northern Russia],” he said without specifying the name of the vessel and the total number of submarines to be overhauled.

According to Dorofeyev, the overhaul of the first Akula class submarine must be completed in two years, and it will rejoin the Russian Navy after sea trials.

The upgraded vessels will feature better “stealth” capabilities and improved electronics, the official said.

Together with Project 885 Yasen (Graney) class nuclear-powered vessels they will constitute the core of the Russian fleet of nuclear attack submarines.

Akula class submarines feature very low acoustic signatures and can carry up to 12 submarine-launched cruise missiles with nuclear warheads and a range of 3,000 km (1,860 miles) in addition to anti-ship missiles and torpedoes.