Oil prices fell on Tuesday following reports that output by the Organization of the Petroleum Exporting Countries (OPEC) rose last month despite the cartel's agreement to reduce production.

Tanker-tracking firm Petro-Logistics said Tuesday OPEC's output was up by 145,000 barrels a day last month, according to media reports.

Major oil producers have agreed to reduce supply by 1.8 million barrels a day through next March. The goal is to shrink global stockpiles, balance the market that has seen oversupply lingering for about three years and eventually raise oil prices.

The West Texas Intermediate for September Delivery lost 1.01 U.S. dollars to settle at 49.16 dollars a barrel on the New York Mercantile Exchange, while Brent crude for October delivery erased 0.94 dollar to close at 51.78 dollars a barrel on the London ICE Futures Exchange.