China’s Sinopec, Asia’s largest refiner, plans to cut Saudi crude oil imports loading in May by 40 percent after national oil company Saudi Aramco set higher-than-expected prices, an official from the company’s trading arm Unipec said. “Our refineries think that these are unreasonable prices as they do not follow the pricing methodology,” the official, who declined to be named, said on Monday. Asian oil traders have struggled to understand how Saudi Arabia derived its official selling prices (OSPs) for May after the world’s top oil exporter unexpectedly raised the price for its flagship Arab Light crude sold to Asian refiners.