U.S. drivers are facing the highest pump prices in two months, a consequence of the costlier crude oil used to make the fuel. Domestic retail gasoline averaged $2.19 a gallon on Wednesday, up about 5 cents so far this month, according to auto club AAA. Crude is the culprit. Benchmark crude futures in the U.S. are the most expensive in months, following a rally fueled in part by optimism around the impending circulation of Covid-19 vaccines.

Gasoline prices rise through December

The crude needed to produce gasoline “is climbing due to the vaccination availability and promise that distribution is building toward being more widely available in 2021,” said Jeanette Casselano, a spokeswoman for AAA.

Front-month West Texas Intermediate crude futures are up about $6 a barrel since mid-November. Gasoline futures are trading at the highest since August.