ReutersOil is back at $50 a barrel. The Brent Crude price just popped above the threshold in the Asian trading session, following a steady rally over recent weeks which has been driven by a range of global supply constraints. It’s the first time Brent has been above $US50 since November last year. Today’s rally in Asia builds on two solid days of trade on European and North American markets after Energy Industry Association inventory data showed inventories fell 4.226 million barrels against expectations of a just 2.5 million barrel draw.