Saudi Arabia is expected to slash the prices for its crude bound for Asia in January to the lowest premium to benchmarks in five years, as the world’s largest crude exporter looks to preserve market share amid ample supply and falling spot Middle East benchmarks. Saudi oil giant Aramco will likely reduce the official selling price (OSP) of its flagship Arab Light crude grade by $0.30-$0.40 per barrel to a premium of $0.60-$0.70 a barrel to the average Oman/Dubai benchmark for loadings to Asia in January, a Reuters survey of Asian refining…