A commercial airliner takes off past the air traffic control tower at San Diego International Airport during the first day of a partial U.S. government shutdown in San Diego, California, U.S., October 1, 2025. REUTERS/Mike Blake

By Doyinsola Oladipo and David Shepardson

NEWARK/WASHINGTON (Reuters) -The union representing more than 13,000 U.S. air traffic controllers on Monday urged workers to remain on the job during the ongoing partial government shutdown that requires them to work without pay.

U.S. Transportation Secretary Sean Duffy and the president of the National Air Traffic Controllers Association are holding a press conference on Monday at Newark Liberty International Airport to discuss the impacts of the shutdown. The airport near New York City is a major United Airlines hub.

President Donald Trump has made transportation a focal point in a government shutdown battle with the Democrats, cutting off more than $28 billion of aid for climate programs, subways, tunnels and mass transit in Democratic-leaning states like New York and Illinois.

Last week Vice President JD Vance pulled air travelers into the shutdown debate when he said they "may not arrive on time because the TSA and the air traffic controllers are not getting paid today," on Fox News. No flights are believed to have been delayed because of the shutdown.

In 2019, during a 35-day shutdown, the number of absences by controllers and Transportation Security Administration officers rose as workers missed paychecks, extending checkpoint wait times at some airports. Authorities were forced to slow air traffic in New York, which put pressure on lawmakers to quickly end the standoff.

The union on Monday told workers "participating in a job action could result in removal from federal service" and that it is illegal.

"It is more important than ever that we rise to the occasion and continue delivering the consistent, high-level of public service we provide every day," the union told members. "We cannot stress enough that it is essential to avoid any actions that could reflect poorly on you, our union, or our professions."

About 50,000 TSA employees who staff airport security checkpoints are also required to keep working, but are not getting paid.

NATCA in 2019 said many controllers had reached "the breaking point." Then-House Speaker Nancy Pelosi, a Democrat, said at the time the shutdown was "pushing our airspace to the breaking point."

Airline trade group Airlines for America, which represents United, Delta Air Lines, American Airlines and Southwest Airlines, warned that during a funding lapse "the system may need to slow down, reducing efficiency" and impacting travelers.

A persistent shortage of controllers has delayed flights and many are working mandatory overtime and six-day weeks. The FAA is about 3,500 air traffic controllers short of targeted staffing levels.

(Reporting by David Shepardson; Editing by Bill Berkrot and Chris Reese)