Oil down 1% on weak China GDP data, resumption of Libya output

OIL prices extended their decline into a second session on Monday after China's second-quarter growth came in weaker than expected, fuelling concern about demand in the world's No. 2 oil consumer, while Libya resumed production on the weekend.

Brent crude futures fell 91 cents, or 1.1%, to $78.96 a barrel by 0628 GMT, and U.S. West Texas Intermediate crude was at $74.55 a barrel, down 87 cents, also down 1.1%.