On 28 April 2010, the Ukrainian parliament ratified an agreement to extend Russia's lease of Crimean base facilities to 2042 with an option for five more years, through 2047. Subsequent to the annexation of Crimea by Russia in 2014, this agreement has been officially invalidated by the Russian State Duma. The Russian Navy has also revealed that the Russia's Black Sea Fleet will receive 30 new ships by 2020 and will become self-sufficient with its own infrastructure in the Crimean peninsula. The fleet will be updated with new warships, submarines, and auxiliary vessels within the next six years. The new ships built for the Black Sea Fleet include three "Admiral Grigorovich"-class frigates (originally six, but at least two of the remaining three were sold to India) and six Varshavyanka-class (Improved Kilo-class) diesel-electric submarines.