Russian state inspectors have opened an inquiry into major Russian oil firms suspected of market rigging to push up petrol prices nationally.
Ukraine's Energy Challenge
BBC: Russia opens oil price-fixing probe against top firms
Russia's President Vladimir Putin (L) poses for a photo with Russian oil giant LUKoil president, Vagit Alikperov, during an awarding ceremony in the Kremlin in Moscow, on July 31, 2014.
