World oil prices declined more than $6 in Tuesday's New York trading.
The price of a barrel of oil for future delivery fell to $135.95 at the close of trading, a drop of nearly $10 from the record high of $145.85 set on July 3.
Oil investors may be concerned by signs that the global economy is slowing, which could ease demand for oil.
Demand for gasoline is declining in the United States, the world's largest energy consumer. The MasterCard credit card company says Americans bought nearly four percent less gasoline last week as they did at the same time last year.
Retail gasoline prices have been hitting record highs frequently in the United States, with the most recent record on Monday of $1.08 a liter, or nearly $4.08 a gallon.
Some information for this report was provided by AFP, AP and Reuters.