U.S. retail gasoline prices increased for the first time in three weeks, the government said Monday, as gasoline production came to a halt at more than a dozen refineries along the Gulf Coast because of Hurricane Rita (search).

The national price for regular unleaded gasoline rose 1.7 cents over the last week to $2.80 a gallon, up 89 cents from a year ago, according to a survey of service stations conducted by the U.S. Energy Information Administration (search) (EIA).

The Gulf Coast states, where Rita struck, saw the biggest regional increase in pump costs, up 6.8 cents to an average $2.72 a gallon, the Energy Department's analytical arm said.

EIA senior analyst Doug MacIntyre (search) said consumers should expect some increase in gasoline costs with so many refineries still shut due to Rita, but nothing like the 46-cent price spike at the pump to the record $3.07 a gallon during the week after Hurricane Katrina struck.

President Bush said Monday that about one third, or 1.8 million barrels per day, of the refining production initially shut by Rita will be back online soon.

"The storm affected the ability to get gasoline to markets," he said. Until then, Bush urged Americans to conserve gasoline by cutting back on non-essential driving.

In the weekly EIA survey, the West Coast had the most expensive gasoline by region with the price down 1.9 cents at $2.93 a gallon. San Francisco topped the agency's survey of cities, with the price of gasoline down 1.2 cents at $2.98 a gallon.

The Gulf Coast and Midwest states had the cheapest fuel at $2.72 a gallon, with the price down 4.2 cents in the Midwest region. Among major cities, Houston had the cheapest price, with motor fuel down 2 cents at $2.71.

The EIA report also showed prices, rounded to the nearest penny, down 8.7 cents at $2.91 in New York City, up 0.3 cent at $2.89 in Miami, down 6.4 cents at $2.87 in Boston, down 3.2 cents at $2.86 in Denver, down 1.1 cents at $2.85 in Seattle and down 2.2 cents at $2.79 in Chicago.

Separately, the average price for diesel fuel jumped 6.6 cents to $2.80 a gallon, up 79 cents from a year earlier.

Truckers on the West Coast paid the most for diesel at $2.98 a gallon, down 0.7 cent from last week. The Midwest had the cheapest diesel at $2.74 a gallon, up 9.1 cents.