NEW YORK — U.S. gas prices jumped back to $4 a gallon on average Monday, as Washington's latest fighting with Iran renews strain on the flow of fuel worldwide.
According to motor club AAA, the national average for a gallon of regular gasoline is now just above the $4 mark. That's about 13 cents more expensive than it was a week ago, and far higher than where prices at the pump stood at this time last year, when American drivers could fill up for about $3.14 a gallon on average.
The U.S. and Israel's war with Iran plunged the world into a global energy crisis, notably as the cost of crude oil — the main ingredient in gasoline — soared due to supply chain and production disruptions across the Middle East.
Energy prices cooled last month when Washington and Tehran reached an interim agreement aimed at permanently ending their fighting and reviving traffic in the key Strait of Hormuz. But that peace deal has now crumbled — with the U.S. on Monday only intensifying airstrikes against Iran, which has responded by launching its own attacks on American allies in the region. And oil flows are largely stalling again.
Many eyes are on the White House. Before co-launching the war in late February, President Donald Trump once bragged about keeping gas prices low — and expressed frustration about them not falling as quickly as the cost of crude oil last month. If prices continue to rebound, expensive gas will likely be at the top of voters' minds during the midterm elections this November.
Here's what we know.
Where gas prices stand today
Again, U.S. gas prices are now back at the $4 mark. But that figure is a national average, meaning drivers in some states have been paying well over $4 a gallon for a while now, while others pay less.
California on Monday continued to see the most expensive gas, with an average of nearly $5.50 a gallon — followed by almost $5.42 in Hawaii and $5.01 in Washington state, per AAA. Meanwhile, states like Indiana and Mississippi have averages closer to $3.35 and $3.57, respectively. Prices vary between due to factors ranging from nearby supply to differing tax rates.
Crude oil is the main ingredient in gasoline, and its cost makes up the bulk of what consumers pay at the pump. There's a bit of a delay because refineries buy crude in advance, and deliveries of that oil take time. But the latest gas prices follow an uptick in oil costs seen over recent weeks. The price of Brent crude, the international standard, swung between roughly $86 to $91 a barrel Monday — compared to closer to $72 at the start of July.
Oil has been volatile throughout the course of the war, with prices soaring more rapidly in the conflict's early days. In March, Brent climbed as high as nearly $120 per barrel. Meanwhile, U.S. gas prices hit a four-year record of more than $4.50 a gallon in May.
The national average fell to as low as $3.79 a gallon earlier this month. And the latest turnaround is bringing whiplash to some drivers.
“I am down to the last drops of gas,” said Litza Mavrothalasitis, a Chicago resident, when filling her tank on Monday, adding that she was shocked to see how high it had gone up again. “It was just unbelievable. I thought we were finally settling down.”
Jacob Fisher, another Chicago resident who was buying gas on Monday, added that thinking about what's behind these higher fuel costs “makes me angry.”
“Senseless war in Iran, and our current administration is fueling a lot of this — and it’s terrible,” Fisher said. “It is not serving the American people. Nor does it serve anywhere in the entire world.”
White House's response and the road ahead
White House spokesperson Taylor Rogers said in a statement Monday that “oil and gas prices will plummet back to pre-conflict levels” as the U.S. military degrades Iran’s ability to attack vessels and disrupt trade in the Strait of Hormuz, where roughly a fifth of the world's oil sailed through during peacetime.
“President Trump remains committed to unleashing American energy dominance, cutting costs, and putting more money back in the pockets of hardworking American families,” Rogers added.
Still, the escalation of attacks and confusion over future control of Hormuz has fueled uncertainty. All the while, traffic in the key waterway has stalled — with analysts from S&P Global Energy noting Monday that vessel crossings fell 50% last week compared to the week prior.
“The continued predominance of Iran-linked and sanctioned vessels suggests mainstream shipowners remain cautious about transiting the waterway,” the analysts added.
Even if fighting ends, experts have repeatedly warned it could take months, if not longer, for supply chains to return to prewar levels. Last month, S&P Global Energy said it did not expect Persian Gulf oil production to rebound fully until at least the first quarter of 2027.
Gas isn't the only necessity getting more expensive
Beyond gasoline, fuel like diesel — which powers many freight and long-haul trucks — is also back on the rise. On Monday, diesel averaged at nearly $5.11 a gallon in the U.S., per AAA, up from $4.88 just a week ago.
American households have already collectively paid nearly $71.1 billion in extra costs for gas and diesel alone since the war began, according to an online tracker from Brown University’s Watson School of International and Public Affairs.
Beyond pain at the pump, higher fuel prices raise transportation costs across businesses. And shortages of other core necessities — like fertilizer — have also worsened amid the war. Groceries, airline tickets and even goods like condoms and shoes have gotten more expensive in recent months.
Supply shocks have been even starker in places that rely more heavily on imports from the Middle East — notably countries across Asia and Africa.
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AP journalists Laura Bargfeld in Chicago and Matthew Daly in Washington contributed to this report.
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