Refiners on the U.S. West Coast and Hawaii have stepped up purchases of Russian crude, taking advantage of a narrow gap between U.S. and global prices as they look to guard against a seasonal shortage of Alaskan supply, trade and industry sources said. Up to four tankers were expected to carry nearly 3 million barrels of Russia’s ESPO crude from Kozmino near the city of Vladivostok to refineries in the United States this month and next, the sources said. That will help Russia diversify beyond key buyers in China, South Korea and Japan at a time when Asian markets are grappling with oversupply. Sanctions against Russia over its actions in Ukraine bar U.S. oil companies from drilling in the country, but purchases of oil are still allowed. But traders said the shipments marked only a temporary trend as refineries were buying amid uncertainty over the supply of Alaska […]