CAMARILLO, Calif. (AP) — A survey says the average price of a gallon of regular gasoline in the U.S. has risen by 2 cents over the last two weeks to $3.71.

Industry analyst Trilby Lundberg said Sunday that crude oil prices rose over jitters about Iraqi oil production as violence there grows.

Much of that increase hasn’t been passed on to consumers yet, and prices could increase over the coming weeks.

The survey taken Friday shows the average price for a gallon of midgrade gas was $3.90 and the average price for a gallon of premium was $4.05. Diesel averaged $3.95 a gallon.

Of cities surveyed in the continental U.S., Tucson, Arizona, had the lowest average price at $3.37 a gallon. Chicago had the highest average at $4.15 a gallon.

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