The national average price of a gallon of regular unleaded increased five cents for the week to $2.66, and has jumped 11 cents in the past two weeks as fuel stations purge their winter blend gasoline, reports AAA.

Less than four of every 10 stations (38%) are now selling gasoline for $2.50 or less, said Jeanette Casselano, AAA spokesperson.

"That percentage will likely dwindle in coming weeks," she said. "The holiday weekend, strong demand and preparation for summer gasoline are all factors that have driven and will continue to drive higher gas prices into early spring."

While the price moved higher, demand fell to 9.2 million barrels per day, according to data from the U.S. Energy Information Administration. Demand has reached a March trough, but remains strong for this time of year.

States with the largest weekly increases included Utah (up 14 cents), Kentucky (up 10 cents), Missouri (up nine cents), Florida (up nine cents), and Arizona (up nine cents).

States with the most expensive markets include Hawaii ($3.52), California ($3.51), Washington ($3.17), Alaska ($3.13), Oregon ($3.09), and Nevada ($3.01).

Meanwhile, the average price of a gallon of diesel increased 3.2 cents to $3.042, which was 48.6 cents above a year ago.