The surging price of jet fuel isn’t the airline industry’s only problem. Now, it’s whether it will have enough.

Since the U.S. and Israel attacked Iran on Feb. 28, the price of jet fuel in the U.S. has nearly doubled, going from $2.50 a gallon on Feb. 27 to $4.88 a gallon on April 2, with the increases even sharper in other regions. The effective closure of the Strait of Hormuz is choking off supplies of both crude and refined products like jet fuel, further driving up the price.

That’s forcing airlines to consider cutting flights, especially overseas.

Carsten Spohr, CEO of Germany’s Deutsche Lufthansa, told employees in a webcast last week that the carrier is assigning teams to come up with contingency plans because of the war in the Middle East, including for drops in demand or a lack of jet fuel, a spokesman said. Those plans could include grounding some of its aircraft.

The U.S. produces a lot of jet fuel and isn’t as exposed as other regions like Europe and parts of Asia are in comparison. But aircraft fill up locally, so some U.S. airlines could face shortages on international trips.

United Airlines CEO Scott Kirby told reporters late last month that the carrier, which has the most service to Asia among U.S. airlines, would have to cut back its flights there. He also said it’s “not impossible” that airlines collectively would have to reduce service in that region.

He noted that as the price of jet fuel goes up, it could be more acute in parts of the U.S. that aren’t as connected by pipelines.

“There’s not enough refining capacity, and so fuel price prior to this and going forward is more susceptible to supply weakness on the West Coast than anywhere else in the country,” he said.

Kirby told employees earlier in March that the airline is preparing for oil to stay above $100 a barrel through 2027 and is pruning some of its flights in the near term.

“To be clear, nothing changes about our longer-term plans for aircraft deliveries or total capacity for 2027 and beyond, but there’s no point in burning cash in the near term on flying that just can’t absorb these fuel costs,” he said in a March 20 message to employees.

Investors will be listening for more insights into how the jet fuel spike could affect the industry as airline earnings kick off Wednesday with Delta Air Lines. That carrier owns a refinery, so it could benefit from jet fuel sales.

Delta on Tuesday raised checked bag fees, joining JetBlue Airways and United, which did the same last week.

The strong demand, particularly compared with this time last year could further insulate airlines, at least in the U.S. Last year, bookings fell as President Donald Trump‘s trade war kicked off with steep tariffs, markets sank and layoffs within the government, led by Elon Musk‘s so-called Department of Government Efficiency, took effect.

“The positive commentary on demand is still holding, but fuel at $4/4.50 [a gallon] for longer isn’t something airlines can pass through,” said Savanthi Syth, an airline analyst at Raymond James. “If fuel stays high, you’ll just see capacity being cut.”

Airlines could see a bigger problem if higher gasoline prices and other pressures on consumers cause a pullback in spending.

“We’re watching the airlines very closely right now. This doesn’t have to go on too terribly long at these [fuel price] levels before you start to see potential for ratings pressures,” said Joseph Rohlena, senior director at Fitch Ratings who covers U.S. airlines.

Levi Strauss saw another quarter of strong sales, helped in part by higher prices, and direct-to-consumer sales made up more than half of its overall revenue — a milestone for a company that has long relied on wholesalers.

The denim maker’s revenue grew by 14% while DTC sales through Levi’s own stores and website jumped 16%, bringing total DTC sales to 52% of overall revenue.

In an interview with CNBC, CEO Michelle Gass said she expects DTC revenue to make up more than half of overall sales for the duration of the year, even as its more traditional wholesale channel continues to grow.

The growth is not from increased sales volume alone: Levi is benefiting from higher prices and positive foreign exchange headwinds. Finance chief Harmit Singh, who announced plans to retire on Tuesday, said about half of Levi’s growth is related to recent price increases and half is tied to actual units sold.

Given its first-quarter beat, Levi raised its guidance. It’s now expecting full-year adjusted earnings per share to be between $1.42 and $1.48, shy of expectations of $1.47 per share on the low end, according to LSEG.

It’s expecting sales to rise between 5.5% and 6.5%, largely ahead of estimates of 5.6%, according to LSEG. 

Here’s how the apparel maker did in its first fiscal quarter compared with what Wall Street was anticipating, based on a survey of analysts by LSEG:

• Earnings per share: 42 cents adjusted vs. 37 cents expected 
• Revenue: $1.74 billion vs. $1.65 billion expected 

The company’s reported net income for the three-month period that ended March 1 was $175.8 million, or 45 cents per share, compared with $135 million, or 34 cents per share, a year earlier. 

Sales rose to $1.74 billion, up about 14% from $1.53 billion a year earlier. 

Levi’s DTC-first strategy comes with bigger margins but also higher costs in the short term as it changes its distribution system, which has weighed on earnings. However, Singh said its sales are becoming more profitable as DTC scales.

He also noted that Levi’s guidance could rise later in the year. Currently, it’s assuming a 20% global tariff, though President Donald Trump has for now set a 10% duty on U.S. imports after the Supreme Court rolled back so-called reciprocal tariffs earlier this year. If that 10% tariff remains in effect, it could boost full-year earnings by $35 million, or 7 cents per share. The company could also be refunded as much as $80 million after the Supreme Court struck down Trump’s previous global tariff policy, Singh said.

While that could boost earnings, Levi could face weaker sales in the coming months as consumers digest higher gas prices and consider pulling back on nice-to-haves like new clothes. Gass told CNBC she has not seen a pullback in spending so far, and the business is segmented in a way that it’s reaching a wide array of consumer demographics.

For example, Levi’s value brand Signature saw sales rise 16% during the quarter and its middle market Red Cap was up 9%, while its premium line Blue Tab is also growing, said Gass.

“We talked about over the last couple years, we made big, bold moves like selling Dockers and other brands and businesses. Now we’re really focused on segmentation around the Levi’s umbrella,” said Gass. “We feel like we’re really covered to serve the consumer across really every demographic and psychographic cohort and I think the other piece is, when we think about our business globally, 60% of our business is outside the U.S., which also gives us some really nice diversification. So we’re watching it closely, but overall, we’re feeling good about the consumer.”