Delta Air Lines Inc. said it will boost fares and add fewer flights than planned, as carriers contend with a surge in fuel prices that is looming over flush times for the industry.

Delta on Thursday posted second-quarter earnings than topped forecasts, with record revenue helping to offset a $578 million jump in its fuel bill, up 33% from a year earlier on an adjusted basis.

But the No. 2 U.S. carrier by traffic said those rising fuel costs will weigh on profit for the rest of this year, leading it to lower its profit outlook. Delta said its fuel bill in 2018 would be $2 billion higher than last year.

“With higher fuel prices you’re going to expect to see ticket prices go up as well,” Chief Executive Ed Bastian said.

Analysts expect other U.S. carriers to outline plans to restrain capacity as they report earnings over the next few weeks. Airline shares fell sharply on Wednesday after American Airlines Group Inc., the No. 1 U.S. carrier, warned that its revenue per available seat mile, a key industry metric, would fall short of its previous guidance. That day, American’s shares fell 8% to their lowest level in nearly two years.