Inflation rose sharply in April, driven largely by steep increases in energy costs as President Donald Trump’s war with Iran continues.

The consumer price index rose by 3.8% in April from the previous year, according to the U.S. Bureau of Labor Statistics. Of that, the price of energy increased 17.9% over the last year.

Gas prices rose 5.4% in April after spiking 21.2% in March. And the price of gas is up 28.4% year over year.

Energy costs account for nearly half of the consumer price increases in the April report, with prices increasing by 3.8% in April, following an almost 11% increase in March.

On Monday, the Energy Department announced it planned to release 53.3 million barrels of crude oil from the Strategic Petroleum Reserve to meet ongoing demand as the war constrains global supplies.

The conflict in Iran, specifically the battle over the Strait of Hormuz, has created a fuel crisis that is growing increasingly unpopular with voters. A new CNN poll found that 77% of Americans say Trump’s policies have increased their community’s cost of living, including a majority of Republicans. Trump’s approval rating on the economy is 30%, the lowest of his presidency in the CNN survey.

The April consumer price report, one economist said, is a sign that the Iran war is affecting multiple sectors of the economy, and he warned the increases don’t appear to be abating anytime soon.

“It might be the start of higher energy prices starting to creep through the economy, because you need energy for shipping and transportation and fertilizer to make anything else,” Ryan Young, a senior economist and director of publications at the Competitive Enterprise Institute, told NOTUS.

Young added that even if the war ended today, “it would be at least a year before we’re back to normal.”

Trump said Monday he was in favor of suspending the gas tax, a move that would require congressional approval. The proposed suspension of the 18-cents-a-gallon tax appeared to have support from some Republican lawmakers, NOTUS’ Jenna Monnin reported.

Affordability is shaping up to be a key factor with voters as the November midterms approach and the parties battle for control of Congress.

“The important thing to remember in these situations is the worst kind of inflation is unanticipated inflation, since prices and wages can’t easily adjust,” Judge Glock, the director of research and a senior fellow at the Manhattan Institute, told NOTUS. “This kind of sudden and high inflationary spike can be particularly disruptive to the economy, especially for workers whose wages don’t keep up.”