Oil prices drift lower on China demand worries

Oil prices drifted lower on Friday after a rally the day before, as geopolitical tensions and disruptions in U.S. oil production from a cold blast were countered by concerns over slow demand growth in China. Brent crude futures fell 17 cents, or 0.2%, to $78.93 a barrel by 0151 GMT, and U.S. West Texas Intermediate crude futures (WTI) slid 3 cents to $74.05. Both benchmarks, which gained about 2% on Thursday as the International Energy Agency (IEA) joined producer group OPEC in forecasting strong growth in global oil demand, are on track to end the week around 1-2% higher.