WASHINGTON (Reuters) - The trade group for major U.S. airlines on Tuesday urged the government to act quickly to address a long-standing air traffic controller shortage ahead of the busy summer travel season but the U.S. Federal Aviation Administration chief accused the group of trying to deflect responsibility for flight delays.

Nick Calio, head of Airlines for America, whose members include American Airlines, Delta Air Lines, United Airlines and Southwest Airlines, said the staffing shortage "has a direct impact on airline operations and the traveling public."

FAA Deputy Administrator Katie Thomson rejected the criticism, saying the agency is working to boost hiring and "focused on the safety of the flying public. Rather than funding publicity stunts, we'd welcome support in a serious effort to help recruit more controllers."

Thomson added the "industry's own data shows that weather and airline issues cause far more delays than air traffic control capacity." The FAA points to delays tied to airline staffing and maintenance issues as a bigger issue.

In March, President Joe Biden's administration said it was seeking funding from Congress to hire another 2,000 air traffic controllers in the 2025 budget year after a series of near-miss incidents.

Airlines and the administration have sparred over the last three years over a series of issues, including mergers, consumer rules and family seating.

Calio on Tuesday reiterated calls for action, saying it was "past time" for Transportation Secretary Pete Buttigieg and FAA Administrator Mike Whitaker to "take action to solve this crisis and increase staffing."

A persistent shortage of controllers has delayed flights. At many facilities, controllers are working mandatory overtime and six-day weeks to cover staffing shortages. The FAA wants $43 million to accelerate hiring and training of controllers.

Staffing issues forced the FAA to extend cuts to minimum flight requirements at congested New York City-area airports through October 2024 - allowing airlines to fly fewer flights without forfeiting take-off and landing slots. Airlines have asked for the waiver to be extended by another year.

An independent report in November called for "urgent action" to bolster the FAA, saying the agency has been "asked to do more with less in an already strained system." Whitaker this month agreed to delay new rest requirements for controllers after union objections.

A USDOT inspector general's report in June 2023 found critical air traffic facilities facing significant staffing shortages, and posing risks to air traffic operations.

(Reporting by David Shepardson; Editing by Chris Reese and David Gregorio)

By David Shepardson