"The Yury Dolgoruky will complete an initial sea trial on June 7. If all testing goes successfully, the boat will be accepted into service in the near future," a Sevmash source told RIA Novosti, adding that no tests of the boat's future primary armament, the Bulava ICBM, are planned during the sea trial.

The Bulava will be test-fired again this year, but from another boat of this class, the Alexander Nevsky, and if the test is successful, the two systems will be accepted into the service this year.

Defense Minister Anatoly Serdyukov and former navy commander Admiral Vladimir Vysotsky have previously said that the Borey class boats and Bulava, would enter service this fall.

The 24,000 ton displacement Borey class boats will carry 16 Bulava missiles. The new boats will be the mainstay of Russia's naval nuclear deterrent fleet after 2018, replacing the existing Project 941 and Project 667 (NATO Typhoon and Delta-3 and Delta-4) class ballistic missile submarines.