Oil prices dropped on Friday and were headed toward their fourth consecutive monthly fall as another round of monetary stimulus from Japan pumped up the U.S. dollar and pounded a crude market already suffering from robust supply.
Further pressure came from monthly surveys showing the Organization of the Petroleum Exporting Countries made almost no effort to curb production this month even as oil prices extended a months-long rout to four-year lows.
OPEC's output in October dipped by just 120,000 barrels per day, according to a Reuters survey published Friday. The downtick was led by Angola and Nigeria, with overall OPEC production still hovering 720,000 barrels per day above its 30 million barrels a day target.
U.S. and Brent crude fell by about a dollar to put them both on pace for the steepest monthly decline since May 2012, and the longest monthly losing streak since 2008.
Brent for December was down 92 cents at $85.32 a barrel in late morning trade, after holding below $84 throughout much of the morning. The oil benchmark has fallen more than 10 percent so far in October, its biggest monthly drop since May 2012.
U.S. crude was down 79 cents at $70.33 per barrel, after dipping as low as $79.55 in mid-morning trade. It has lost 12 percent this month.