Gasoline prices across the United States have climbed above $4 per gallon for the first time in nearly four years, as the ongoing war involving Iran continues to drive up fuel costs.

According to the AAA motoring organization, the national average price for a gallon of regular gasoline has reached $4.02—an increase of more than $1 since the conflict began. Diesel prices have also risen sharply, up roughly $1.70 over the same period.

A major factor behind the surge is the effective shutdown of the Strait of Hormuz over the past month. The critical shipping route’s closure has disrupted energy production and transportation throughout the Middle East, slowing or halting supply flows.

As a result, crude oil prices—an essential component in gasoline and diesel—have surged significantly.

Lower fuel prices were a central promise of President Donald Trump’s 2024 campaign. He has since characterized the current spike as a short-term disruption unlikely to have lasting consequences.

However, economists are increasingly cautioning that sustained high fuel costs may force households to cut back on spending, raising concerns about broader economic strain.

"If the conflict is contained soon, the hit to confidence may be temporary," analysts at Moody's Ratings Agency wrote in a recent note. "But a prolonged crisis could prompt more precautionary saving and further discretionary spending cuts."

Before the conflict erupted on February 28, the average price of gasoline stood at about $2.98 per gallon.

Diesel, a key fuel for transporting goods, averaged $3.76 at that time. It has now climbed to $5.45 per gallon, a jump expected to contribute to rising food prices.

AAA also noted that seasonal demand tied to spring break travel has added pressure to fuel prices in recent weeks.

The current average of $4.02 marks the highest level since August 2022. Because it reflects a nationwide average, drivers in certain states have already been paying above $4 per gallon.

Even so, prices remain below the all-time highs recorded in June 2022, when gasoline reached $5.01 per gallon and diesel peaked at $5.81 following Russia’s invasion of Ukraine.

Still, the present increase may have a more pronounced effect on consumers, said Christopher Hodge, chief US economist at Natixis CIB.

"Consumers are in a much weaker position now than they were in 2022," he said, pointing to stronger wage growth and higher household savings during the pandemic period.

Oil markets are also experiencing sharp gains, with Brent crude—the global benchmark—approaching $120 per barrel. Meanwhile, West Texas Intermediate, the US benchmark, has surpassed $100 per barrel for the first time since 2022.

Analysts warn that further increases could have serious consequences. In a report released last week, Oxford Economics senior US economist Matthew Martin said that oil reaching $140 per barrel for an extended period could push the economy into a downturn.

"The duration of the war is the key variable: the longer it persists, the more likely something breaks," he said.

Rising wholesale energy costs typically appear first in fuel prices, a trend now evident not only in the US but globally.

In the United Kingdom, petrol prices have increased by 14% since the war began, while diesel has risen by 27%.

Some countries have already taken emergency measures. Sri Lanka and Bangladesh have introduced fuel rationing, and Slovenia became the first European Union nation to follow suit last week.

Elsewhere, Australia has cut fuel sales taxes in half for three months to ease the burden on drivers, while two states are offering temporary free public transportation to discourage car use.