Gasoline prices surged to the highest level since 2008 on Sunday, as crude oil supply fears stemming from Russia’s war on Ukraine increase the impact on consumers at the pump.

The national average for a gallon of gas hit $4.009 on Sunday, according to AAA, which is the highest since July 2008, not adjusted for inflation. Prices have been rising at a fast clip. Consumers are paying 40 cents more than a week ago, and 57 cents more than a month ago.

In some places, consumers are paying much more. California’s average is now $5.288 per gallon.

The jump in prices follows a surge in the price of oil amid Russia’s war on Ukraine. The underlying cost of oil accounts for more than 50% of the cost of gas that consumers put in their cars, and U.S. oil is trading at levels last since in 2008.