China and its crude oil buying behavior in the spring and summer have stabilized global oil markets as Beijing, not OPEC, is calling the shots now, according to Igor Sechin, chief executive of Russia’s biggest oil producer Rosneft. China has strengthened its position of the ultimate swing buyer on the global market and has taken the initiative from OPEC, said the executive, who is considered to be a close ally of Vladimir Putin and who has been a long-time critic of OPEC. “China has successfully turned from a major consumer and importer…