SACRAMENTO, Calif. (AP) — California Gov. Gavin Newsom is in a spat with a major oil company over who is to blame for the state’s high gas prices, with the Democratic governor’s office urging drivers not to fill up at Chevron stations over Memorial Day weekend.

“Pro tip: unbranded gas comes from the same refineries, storage tanks, and pipelines, and it meets the same state standards to keep your engine running clean,” Newsom’s office posted Thursday on X. “Big Oil is already making billions off Trump’s Iran War; don’t let them rip you off even more by overpaying for the brand name.”

Newsom’s office cited an analysis by a group within the state’s energy commission, which oversees the oil and gas industry, that found that Chevron averaged more than 60 to 80 cents per gallon above unbranded alternatives.

The call-out follows Chevron posting signs at California gas stations blaming the state’s climate policies for the high cost of gas. The average price of gas in California sat at $6.14 per gallon on Thursday, about $1.58 higher than the national average, according to the American Automobile Association. The state taxes consumers about 70 cents per gallon of gas, according to the state’s energy commission. That is the highest gas tax in the country.

“California politicians are choosing foreign oil and fuels over local jobs and lower costs,” the signs read. They feature a QR code that directs to a Chevron webpage asking people to “speak up for affordable, reliable energy.”

It is not clear when Chevron put the signs up, but spokesman Ross Allen said they are part of a campaign the company launched three years ago to inform drivers on the price impacts of California policies.

“We’ve been very vocal about the importance of customer education in California so that our drivers and our consumers understand where their tax dollars are going,” Allen said.

There are hundreds of Chevron gas stations operating in California, and most of them are operated independently and set their own prices, he said.

Memorial Day is typically one of the busiest travel weekends of the year.

Prices at the pump have swelled nationwide since the Iran war began, launching a global energy crisis. The price of crude oil, which is the main ingredient in gasoline, has climbed during the war because the Strait of Hormuz, the narrow passage of the Persian Gulf through which a fifth of the world’s crude oil normally passes, has effectively been shut. Oil tankers have been stranded there unable to deliver crude.

Newsom, who often touts the state’s status as a global climate leader, has passed policies in recent years aimed at cracking down on oil company profits and reducing gas prices.

He signed a law in 2023 allowing the state’s energy commission to penalize oil companies for excess profits, declaring the state had “finally beat big oil.” But regulators voted last year to hold off on plans to penalize businesses until 2030 and prioritize other efforts to protect consumers at the pump.

The postponement came after two oil refineries that accounted for roughly 18% of the state’s refining capacity announced their plans to close, reigniting debate over the price impacts of the state’s ambitious climate policies.

Newsom signed another law in 2024 giving the commission the authority to require refineries to keep a certain amount of fuel on hand. The goal is to try to keep prices from increasing suddenly when refineries go offline for maintenance. But that regulation has also stalled.

Sophie Austin, The Associated Press