If flight suspensions continue, next week’s flight cancellations will get worse.

U.S. airlines will have to cut hundreds more flights next week if Congress fails to find a solution to end what is currently the longest government shutdown in U.S. history.

Trump administration officials this week ordered airlines to begin reducing flights at 40 busy U.S. airports on Friday, citing “increasing reports of system strain from both pilots and air traffic controllers.”

Air traffic controllers and airport security inspectors are required to work without receiving regular pay during the closure. Federal employees’ union says they will not receive their second full paycheck on Monday. According to union officials, some air traffic controllers work part-time jobs to make ends meet.

According to aviation data firm Cirium, 931 of 25,375 U.S. flights were canceled on Saturday.

Under the FAA’s order, the reduction will be 6% of the schedule, expanding to 8% by Thursday and 10% next Friday. Transportation Secretary Sean Duffy told Fox News on Friday that cuts could amount to as much as 20% of the schedule at some point, but did not provide details.

The airline has waived date change fees for travelers on affected flights and said they can also request refunds. Airline executives said many customers were forced to rebook on other flights, while last-minute changes caused other airlines to scramble to make alternative arrangements. hertzFor example, on Thursday, the day the FAA announced flight reductions, it said spending on one-way rental cars jumped 20% compared to the same two days a year earlier.

Delays are also on the rise, with 2,156 flights delayed, according to FlightAware. On Saturday, air traffic control staffing shortages caused delays at airports including San Francisco International Airport, New York’s John F. Kennedy International Airport, New Jersey’s Newark Liberty International Airport and Chicago O’Hare International Airport.

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