United Airlines is raising its fees for first and second checked bags, becoming the second U.S. airline to up the price this week.

United is raising the price by $10 for flights in the U.S., Mexico and Canada and Latin America, the airline said Thursday in a statement, making the price for the first checked bag $45 for those who pay ahead of time and $50 for travelers who check their bag within 24 hours of their flight. The price for a second checked bag also gets bumped up to $55 for those who pay in advance and $60 for those checking within 24 hours.

The change will not apply to customers who bought tickets before Thursday, April 3, the airline said.

“United Chase credit card holders, MileagePlus Premier members, active military members and customers traveling in premium cabins can still check a bag for free,” United said, noting this was the first time it had raised the price for checked bags in two years.

United did not say why it was raising its prices, but the move follows JetBlue also hiking its checked bag fees earlier this week, citing “rising operating costs.” 

Airlines have been contending with the rising price of fuel amid the Iran war. Oil supplies have been constricted due to the closure of the Strait of Hormuz, causing costs to soar. 

Oil prices also jumped following President Trump’s remarks about the war on Wednesday. Brent crude, the international standard, rose 7.7% to $109 per barrel Thursday afternoon, while benchmark U.S. crude climbed 11.9% to $111.81.  

United Airlines CEO Scott Kirby last week told CBS News senior transportation correspondent Kris Van Cleave that elevated oil prices “create a lot of stress” for airlines, noting that United’s airfares have increased between 15% to 20% over the past month.