Benchmark crude traded in New York fell 12 cents to finish at $96.15. Brent crude traded in London fell, too, down 28 cents to $113.31. Brent crude is used to price international varieties of oil.
The Obama administration has been considering a release of oil from the Strategic Petroleum Reserve to dampen the rise in oil prices, which are up more than $8 per barrel this month. Releasing reserves would boost the supply of oil, which would drive prices lower.
On Friday, the trade publication Petroleum Economist reported, based on anonymous sources, that the International Energy Agency had agreed to endorse a plan to release oil from petroleum reserves. The agency, based in France, did not immediately respond to an e-mail seeking comment, and no one answered its phone.
Earlier Friday, oil prices rose slightly on worries about Tropical Storm Isaac, which has the potential to reach hurricane force in the Gulf of Mexico.
That could disrupt oil production and refining. Already on Friday, BP and oil services company Apache Corp. said they were evacuating some offshore workers from the area.
"I think there's a lot of angst with what's going on in the Gulf right now," said Patrick DeHaan, a senior petroleum analyst for GasBuddy.com.
At the pump, the national average for gasoline rose more than a penny to $3.73. That's about a quarter more than a month ago and 16 cents higher than a year ago.
Among other petroleum products trading on the New York Mercantile Exchange:
— Natural gas fell 10 cents, or 3.5 percent, to $2.70 per thousand cubic feet.
— Gasoline at New York Harbor rose a penny to $3.12.
— Heating oil fell 2 cents to $3.12.