Oil prices fell on Friday on concerns that global trade disputes will slow economic growth and demand for fuel, but losses were limited by U.S. sanctions against Iran which look set to tighten supply.  Benchmark Brent crude oil was down 30 cents a barrel at $71.77 by 0845 GMT. U.S. light crude was 30 cents lower at $66.51 a barrel. Escalating trade tensions are casting a shadow over the outlook for economic growth and pushing up the dollar, the currency in which oil is traded internationally, making it more expensive for consumers using other currencies. Major emerging economies including China, India and Turkey have all seen their currencies slump. “Oil, like other commodities, is responding to dollar strength this morning,” Harry Tchilinguirian, […]