“Western involvement in Russian oil and gas plays is more pronounced than ever…Russian state-owned oil and gas giants Rosneft and Gazprom have increasingly allowed Western majors like BP, Eni, Exxon, Shell, Statoil, and Total access to some of Russia’s underdeveloped, but prized projects. Western companies have an estimated $35 billion tied up in Russian oil with hundreds of billions more planned and service providers Halliburton and Schlumberger each derive approximately five percent of their global sales from the Russian market. The Western majors remain committed to their extra-national ventures and these powerful relationships ultimately limit the sanctions’ scope.”
http://oilprice.com/Energy/Oil-Prices/Russia-Can-Survive-An-Oil-Price-War.html