In Washington, President Bush renewed his call to open U.S. coastal waters to oil and gas development to boost production and bring prices down. Florida Gov. Charlie Crist dropped his long-standing support for the federal government's moratorium on offshore drilling.

At the pump, the average national price of a gallon of gas slipped 0.3 cent overnight to $4.075 a gallon, according to a survey of stations by AAA and the Oil Price Information Service. It was the second straight decline, bringing prices half a cent below their latest record of $4.08 a gallon, set Monday.

"I think retail prices ... are as close to stasis based on crude prices as they can be," said Tom Kloza, publisher and chief oil analyst at the Oil Price Information Service in Wall, N.J.

With demand for gasoline falling steadily since January, retailers have had a hard time hiking gas prices fast enough to keep up with rising crude prices. While oil prices have risen 94 percent over the past year, and set a new record of $139.89 a barrel early this week, gas prices are up only 36 percent. That discrepancy has put pressure on the profit margins of companies all along the gasoline supply chain, including refiners, distributors and retailers.

Midwest flooding may create a new wrinkle in the gas price equation; corn and ethanol prices are rising as a result of crop damage and transportation bottlenecks. Rising prices for ethanol, which is used as a gasoline additive, could push gas prices still higher, or limit their declines.

"If you're going to be using less ethanol, you're going to be using more oil," Flynn said.

In other Nymex trading, July gasoline futures rose 4.88 cents to settle at $3.4667 a gallon, and July heating oil futures rose 3.78 cents to settle at $3.86 a gallon.

July natural gas futures rose 25.8 cents to settle at $13.21 per 1,000 cubic feet. Natural gas prices last settled over $13 in December 2005, as they were receding from a spike above $15 in the wake of hurricanes Katrina and Rita.

In London, August Brent crude rose $2.72 to settle at $136.44 a barrel on the ICE Futures Exchange.