MOSCOW, April 4 (RIA Novosti) - Russia will put its first Borey-class strategic nuclear submarine through sea trials in the second half of 2008, the Russian Navy commander said on Friday.

The fourth generation Yury Dolgoruky was built at the Sevmash plant in the northern Arkhangelsk Region and was taken out of dry dock last April. It will be equipped with Bulava ballistic missiles upgraded from Topol-M (SS-27) missiles.

"The Yury Dolgoruky will go to sea in July. If not in July, then in October or November," Adm. Vladimir Vysotsky said.

The submarine has a length of 170 meters (580 feet), a body diameter around 13 meters (42 feet), and a submerged speed of about 29 knots. It can carry up to 16 ballistic missiles.

Two other Borey-class nuclear submarines, the Alexander Nevsky and the Vladimir Monomakh, are currently under construction at the Sevmash plant.

Last year, Russian President Vladimir Putin said that fourth-generation submarines armed with Bulava missiles would form the core of Russia's fleet of modern submarines.