Recent diplomatic progress with Syria was seen as a sign supply lines would remain operational. Traders also interpreted reports Iranian President Hassan Rouhani said his country will never build nuclear weapons as a sign that more oil could be available to meet demand.
On the New York Mercantile Exchange, West Texas Intermediate crude oil for October delivery lost 1.6 percent or $1.72 to reach $104.67 per barrel. Reformulated blendstock gasoline prices dropped 0.97 cents to $2.6875 per gallon. Home heating oil gained 0.33 cents to $3.0073 per gallon. Natural gas dropped 3 cents to $3.69 per million British thermal units.
At the pump, the national average price of unleaded gasoline fell to $3.491 per gallon Friday from Thursday's $3.494, AAA's Daily Fuel Gauge Report said.