The average price for a gallon of regular gas in Maine rose to nearly $4.50 Tuesday, charting a new high since the conflict in Iran began more than two months ago.

Statewide, a gallon of regular averaged $4.48 Tuesday, according to data aggregated by motor club AAA. Premium was up to $5.48 per gallon, and diesel was $5.82.

Tuesday’s average gas price marks a more than 53% increase — about $1.57 — for regular unleaded prices since the end of February, when the United States and Israel first launched attacks against Iran. During that same period, premium gas prices rose about 39% and diesel about 35%.

Experts have warned that rising diesel prices could have spillover effects on the cost of groceries, dry goods and other industries that require the fuel to produce or ship goods. Though diesel prices remain elevated compared to pre-conflict levels, they have fallen some in the last few weeks from a recent high of around $5.94 per gallon early last month, according to AAA data.

Fuel prices have continued to rise despite the United States and Iran reaching a ceasefire last month. The agreement, widely viewed as tenuous, has been tested several times since its announcement.

For weeks, Iran has kept the Strait of Hormuz effectively closed, choking off a vital shipping channel through which roughly one-fifth of the world’s oil and natural gas typically flows. That’s led to major swings in global oil prices: Brent crude, the international standard, topped $114 per barrel Monday before falling closer to $110 by noon Tuesday.

On Monday, the United States attempted to allow hundreds of ships to begin passing through the channel, drawing fire from Iranian forces, who called the effort a violation of the ceasefire agreement, The Associated Press reported. The United States said two merchant ships bearing its flag safely transited the strait, but other cargo vessels were set ablaze. The U.S. military said it sank six Iranian boats as well.

On Tuesday, the U.S. and Iran both claimed to have control of the strait.

HIGHEST IN YEARS, PRICES APPROACHING NATIONAL AVERAGE

Maine’s average regular gas prices are at their highest point since August 2022, when Russia’s invasion of Ukraine shocked global energy prices. The state saw its highest-ever average cost that June, when regular exceeded $5.09 per gallon. Diesel set its all-time peak about a month earlier, topping $6.37.

As the conflict in Iran drags on and the strait remains closed, the usual gap between Maine’s gas prices and the national average has narrowed.

One month ago, Maine’s average price of $3.96 per gallon of regular was about 15 cents less than the national average. A year ago, it was about 17 cents less.

On Tuesday, that difference was half a cent.

Four counties — Androscoggin, Oxford, Sagadahoc and Washington — saw average prices above $4.50 for regular gas. At $4.53 per gallon, Washington’s was the highest county-wide average in Maine; Knox county, where regular gas averaged $4.43 per gallon, was the lowest.