Transportation Secretary Sean Duffy announced on Tuesday that parts of the country’s airspace might face closures next week if the ongoing government shutdown persists.

Duffy attributed the 35-day shutdown to Congressional Democrats, warning that if the impasse isn’t resolved by November 11, the nation’s air travel system could descend into “mass chaos.” This chaos may manifest as flight delays, cancellations, and potentially the closure of certain airspace areas due to a shortage of air traffic controllers.

“It’s important to acknowledge that the shutdown introduces more risk into our system,” Duffy emphasized.

Last Tuesday marked the first missed paycheck for air traffic controllers since the shutdown started, with their last payment in mid-October covering only “80 to 90 percent” of their usual salary, according to Duffy. He further stated that air traffic controllers are set to receive a notification this Thursday, indicating a $0 pay stub for the following Tuesday.

This financial strain has compelled many air traffic controllers to seek additional employment to cover basic necessities such as food and transportation, Duffy explained.

“A lot of us can navigate missing one paycheck. Not everybody, but a lot of us can. None of us can manage missing two paychecks,” he said, on what many controllers have told him. 

More than 2,000 flights within, into or out of the U.S. have been delayed so far Tuesday, with more than 60 such flights canceled, according to flight-tracking site FlightAware. 

It is unclear what percentage of those impacted flights are delayed or canceled due to air traffic controller shortages. On Oct. 9, Duffy told Fox Business the share of delays stemming from staffing issues had jumped from its typical mark of 5 percent to 53 percent.

When reached for comment, the Federal Aviation Administration provided a blanket statement that it “slows traffic into some airports to ensure safe operations” amid air traffic controller shortages.

Duffy acknowledged during the press conference, though, that air traffic controller attendance “has been far better than past shutdowns.” In January 2019, during the most recent funding lapse, air traffic controller shortages released in flight delays along the East Coast. 

Duffy also expressed confidence that the country’s air travel system will “recover pretty quickly” once the shutdown ends. 

“Controllers will start to come back to work, hopefully, quickly,” Duffy said.