NEW YORK, Aug. 7 (Xinhua) -- Oil prices fell on Monday as investors were concerned that major oil exporters' output cut deal may not be effective enough.

The West Texas Intermediate for September Delivery lost 0.19 U.S. dollars to settle at 49.39 dollars a barrel on the New York Mercantile Exchange, while Brent crude for October delivery erased 0.05 dollar to close at 52.37 dollars a barrel on the London ICE Futures Exchange.