The West Texas Intermediate for October delivery on Monday lost $0.67 to settle at $46.97 a barrel on the New York Mercantile Exchange, while Brent crude for October delivery erased $0.66 to close at $49.26 a barrel on the London ICE Futures Exchange, Xinhua news agency reported.
Iraq, which has exported more crude from its southern ports in August, will continue to add output, its oil minister said on Saturday, according to media reports.
Oil prices were also under pressure as the dollar index, which measures the greenback against six major currencies, soared to three-week highs in the previous session on speculation that the Federal Reserve may raise interest rates by year-end.
A stronger greenback dents market sentiment as it makes the dollar-dominated oil less attractive for holders of other currencies.
