Oil reserves in Russia

There have been widely varying estimates of proven oil reserves in Russia. Most estimates included only Western Siberian reserves, which have been exploited since the 1970s and supply two-thirds of Russian oil. However, there are potentially huge reserves elsewhere. In 2005, the Russian Ministry of Natural Resources estimated that another 4.7 billion barrels (0.75×10^⁹ m³) of oil exist in Eastern Siberia.^[1] In July 2013, the Russian Natural Resources Ministry made official estimates of reserves available for the first time. According to Russian Natural Resources Minister Sergey Donskoy, as of 1 January 2012, recoverable reserves of oil in Russia under category ABC1 (equivalent to proven reserves) were 17.8 billion tons and category C2 reserves (equivalent to probable and possible) were 10.9 billion tons.^[2]