WASHINGTON — Air traffic controller furloughs scheduled to kick in on Sunday could result in flight delays of more than three hours in Atlanta, as well as significant delays in Chicago, Los Angeles and New York-area airports, federal officials said Thursday.

Without the furloughs, FAA officials could find no way to cut $637 million from the agency’s budget as required by automatic, across-the-board spending cuts approved by Congress, said Michael Huerta, the agency’s administrator. The FAA has warned of flight delays that will vary depending on each airport’s traffic load and situation.

Likewise, the agency sees no way around closing 149 air traffic control towers at small airports that are currently operated under contract for the FAA, Huerta told the Senate Appropriations Committee’s transportation subcommittee. The tower closings will begin June 15.

The furloughs and tower closings were designed “to minimize impacts on the maximum number of travelers,” Huerta said. But he acknowledged, “We’re forced to choose between very unattractive options.”

A key Republican lawmaker accused President Barack Obama and administration officials of deliberately trying to upset the public.

“They want to cause the most pain to the American people out there so they will put pressure on Congress to back away from sequestration (spending cuts),” Rep. Bill Shuster of Pennsylvania told a transportation gathering hosted by the National Journal news magazine. Shuster chairs the House Transportation and Infrastructure Committee.

The FAA’s 47,000 employees — including nearly 15,000 controllers — are scheduled for one furlough day every other week through Sept. 30. That will reduce the number of controller hours on duty and pay by 10 percent, Huerta said.