More than 1,400 flights to, from, or within the US were cancelled on Saturday after airlines were told this week to cut traffic during the federal government shutdown.
Nearly 6,000 flights were also delayed, down from over 7,000 delays on Friday, according to flight tracker FlightAware.
The Federal Aviation Administration (FAA) announced earlier in the week that it would be reducing air travel capacity by up to 10% at 40 of the nation's busiest airports as air traffic controllers, who are working without pay during the shutdown, report fatigue.
Republicans and Democrats remain divided over how to end the impasse in Congress as the shutdown, which began on 1 October, continues.
Saturday marked the 39th day of the longest shutdown in history as Republicans and Democrats still have not agreed on a funding resolution to reopen the government.
Senators are in Washington over the weekend for bipartisan negotiations aimed at ending the shutdown, which is beginning to be felt by more and more Americans amid cuts to food aid payments and flight disruptions.
In a statement on Saturday, American Airlines urged leaders in Washington, D.C., to reach an immediate resolution to end the shutdown.
New Jersey's Newark Liberty International Airport was experiencing some of the longest wait times. As of Saturday afternoon, arrivals to the airport were delayed by an average of more than four hours, while departures from the airport were delayed by an average of 1.5 hours, according to the FAA.
The airports with the most cancelled flights on Saturday, both to and from the location, were Charlotte/Douglas International, Newark Liberty International, and Chicago O'Hare International, according to FlightAware.
Departures to John F Kennedy International, Hartsfield-Jackson Atlanta International, and La Guardia were delayed by nearly three hours, over 2.5 hours, and about an hour, respectively, the FAA reported as of Saturday afternoon.
With the Thanksgiving holiday approaching on 27 November, it's one of the busiest travel seasons of the year in the US.
It's not just commercial flights that have been affected. Restrictions on private jets are also in place. We've reduced their volume at high traffic airports — instead having private jets utilize smaller airports or airfields so busy controllers can focus on commercial aviation, Secretary Duffy stated on X.
On Thursday, the agency announced that the flight reductions would be gradual, starting at 4% of flights on Friday and increasing to 10% by 14 November.
The FAA said the cuts were necessary to maintain safety, as air traffic controllers have been overworked during the shutdown.
Controllers are among the 1.4 million federal workers affected by the shutdown.
Most of the Transportation Security Agency (TSA) 64,000 agents are also not being paid while the shutdown persists.
During the previous government shutdown in 2018, it was found that up to 10% of TSA staff chose to stay home rather than work for free.
