WASHINGTON – The Federal Aviation Administration said that the U.S. air traffic system will resume normal operations by Sunday evening after lawmakers rushed a bill through Congress allowing the agency to withdraw furloughs of air traffic controllers and other workers.

The FAA said it has suspended all employee furloughs and that traffic facilities will begin returning to regular staffing levels over the next 24 hours. The furloughs were fallout from the $85 billion in automatic across-the-board spending cuts this spring.

They started to hit air traffic controllers this past week, causing flight delays that left thousands of travelers frustrated and furious. Planes were forced to take off and land less frequently, so as not to overload the remaining controllers on duty.

The FAA had no choice but to cut $637 million as its share of $85 billion in automatic government-wide spending cuts that must be achieved by the end of the federal budget year on Sept. 30.

Flight delays piled up across the country Sunday and Monday as the FAA kept planes on the ground because there weren’t enough controllers to monitor busy air corridors. Cascading delays held up flights at some of nation’s busiest airports, including New York, Baltimore and Washington. Delta Air Lines canceled about 90 flights Monday because of worries about delays. Just about every passenger was rebooked on another Delta flight within a couple hours. Air travel was smoother Tuesday.

The cuts were required under a law enacted two years ago as the government was approaching its debt limit. Democrats were in favor of raising the debt limit without strings attached so as not to provoke an economic crisis, but Republicans insisted on substantial cuts in exchange. The compromise was to require that every government “program, project and activity” — with some exceptions, like Medicare — be cut equally.

The FAA had reduced the work schedules of nearly all of its 47,000 employees by one day every two weeks, including 15,000 air traffic controllers.