Oil steady as rise in U.S. inventory slows upswing

By Christopher Johnson LONDON (Reuters) - Oil prices steadied on Thursday after a surprise increase in U.S. inventories helped stall an upward trend that has pushed global crude benchmarks to their highest levels since July last year. U.S. light crude was down 15 cents at $53.91 by 1435 GMT while North Sea Brent crude was up 10 cents at $56.32 a barrel. Both crude oil benchmarks have made big gains this month since OPEC and other producers agreed to curb production in an attempt to balance an ov