West Texas Intermediate futures for September delivery declined to $48.20 (-0.66%), while Brent crude slid to $53.11 (-0.38%) after Abdullah El-Badri, Secretary General of the Organization of the Petroleum Exporting Countries, said that the cartel members will maintain current production levels (over 30 million barrels per day). El-Badri also said that rising demand would prevent a further fall in oil prices. On Thursday he met Russia's energy minister in Moscow.

The latest survey by Reuters forecasts Brent price to fluctuate around $60.60 in 2015 and $69% in 2016. WTI average price is likely to be $54.90 this year and $63.80 in 2016.

Gold fell to $1,083.00 (-0.50%). The precious metal approached its lowest level in five and a half years and headed for the sixth weekly decline in a row amid a stronger dollar. The dollar (bullion's opponent) gained after data showed that the U.S. economy expanded by 2.3% in the second quarter vs 2.6% expected. However it's even more important that the first quarter's reading was revised to +0.6% from -0.2%. "That big overhang is enough to keep gold trading at low levels," Argonaut Securities said.

Physical demand remained weak.