Oil rises on tighter market, but doubts swirl on sustainability

Oil prices rose for a third day on Wednesday as Opec said the market was gradually tightening after years of oversupply, but the 2018 outlook was less certain. Brent crude futures LCOc1, the international benchmark for oil prices, were trading at $56.80 per barrel at 1129 GMT, up 19 cents. Brent closed 2% higher the previous day.