Russia’s navy plans to expand its fleet by 50 ships this year as part of a massive military upgrade plan started under President Vladimir Putin last year and is to continue until 2050. Those ships include nuclear submarines to replace Russia’s aging fleet and some refurbished surface ships, the Moscow Times reported.

The navy will receive the second and third of its Borei-class nuclear-powered submarines in 2015 along with at least five new surface warships and 10 combat boats, ITAR-Tass reported. The revamp comes as tensions between Russia and its former Cold War adversaries in the West are at their highest since the collapse of the Soviet Union over the conflict in Ukraine. U.S., Ukrainian and European officials accuse Russia of directly intervening on behalf of pro-Russian separatists in the east of the country.

A majority of U.N. member states condemned Russia’s annexation of Crimea, a Ukrainian peninsula that until its annexation hosted both the Ukrainian and Russian Black Sea fleets. Russia forced the Ukrainian navy out and took command of a number of bases and the equipment at them. Direct control over Crimea gives Russia a more complete presence in the Black Sea across from three NATO member states: Bulgaria, Romania and Turkey.

The Russian navy was slated to receive two Mistral-class helicopter carriers from France no later than this fall, but European sanctions on Russia resulting from the conflict in Ukraine has blocked the final sale of the ships. One Mistral-class ship is completed and Russian sailors trained on it last year. France initially resisted calls to cancel the lucrative contract but agreed to postpone the sales in August.

The Russian navy inherited much of the former Soviet navy following the collapse of the Soviet Union, but years of economic crises have left the navy with little funding to maintain its massive fleet. Former Soviet states like Ukraine faced the same financial difficulty maintaining their large militaries following the USSR's collapse, leaving many with large inventories of dilapidated and mothballed equipment.

The Russian navy currently operates 280 ships and 256 aircraft although many of the former are inactive and run by skeleton crews. Its flagship is its only aircraft carrier, the 25-year-old Admiral Kuznetsov.