Oil prices are slightly lower as investors focus on global economic issues, including the so-called "fiscal cliff" in the US.
Crude lost 42 cents at $85.90 in midday trading in New York.
Expiring tax cuts and broad spending cuts will take effect in January unless the White House and Congress make a deal.
Economists worry that no deal would have a serious impact on the economy.
Slower economic growth means less demand for fuels such as gasoline, heating oil and natural gas.
The Energy Information Administration says crude oil supplies grew less than analysts expected last week.
