Russia's Black Sea Fleet Stringer . / Reuters NOVOROSSIYSK Russia (Reuters) - Russia will increase its Black Sea fleet by 2020 with more than 80 new warships and will complete a second naval base for the fleet near the city of Novorossiysk by 2016, its commander said on Tuesday.

In comments made to President Vladimir Putin as he visited the port city, Vice Admiral Alexander Vitko said a second Black Sea base was needed in addition to the main base on the Crimea peninsula annexed from Ukraine because of NATO expansion.

"Eighty ships and other vessels are expected to arrive (in Novorossiysk) before 2020. The Black Sea Fleet will have 206 ships and vessels by 2020," Interfax news agency quoted Vitko as telling Putin.

"NATO ships are constantly present in the Black Sea and it plans to establish a naval base in the Black Sea," he added.

NATO has regularly conducted naval exercises in the Black Sea, especially since Russia annexed Crimea, populated mainly by ethnic Russians, in March partly from fear that Ukraine's new pro-Western authorities might try to join the Atlantic alliance.

A NATO source said he was not aware of any plans for a new naval base in the region but added alliance member Bulgaria has a Black Sea base that could be used by NATO ships. NATO has two other members with a Black Sea coastline, Romania and Turkey.

The former Soviet republic of Georgia, on the eastern shore of the Black Sea, has sought membership in the past but like Ukraine is very unlikely to be admitted any time soon due to Moscow's fierce opposition to NATO's further eastern expansion.

During NATO exercises in western Ukraine earlier this month, Russian Defense Minister Sergei Shoigu promised to boost the number of troops in Crimea.

Putin plans to spend 21 trillion rubles ($545 billion) by the end of the decade on refurbishing Russia's armed forces. Some of those funds will be used to improve the defense infrastructure of Crimea.

(1 US dollar = 38.5400 Russian rouble)

(Writing by Thomas Grove; Editing by Timothy Heritage and Gareth Jones)