“I’m concerned about their dedication. I’m concerned about their patriotism. And so we haven’t made a decision, but we are going to look at those controllers who continually made the decision not to show up for work, and again, we have to look at the data,” Duffy said.

“I would just tell you, I’m trying to bring more air traffic controllers in. I’m not trying to take air traffic controllers out, but if we have controllers who systemically weren’t doing their job, we will take action,” he added.

Though the government shutdown seems on the verge of ending, Duffy warned on Tuesday that flight cuts could continue well after the government reopens.

“We’re at the cusp of hopefully having the government reopened. I’m concerned that we’re not gonna have, on Day One, controllers come back into the towers right away. I’m asking them to do that. President Trump has asked them to do that. It is their jobs, and they will be paid, but it might not be immediate that they come back in,” Duffy said.

OVER 5,000 FLIGHTS DELAYED OR CANCELED ON SECOND DAY OF FAA CUTS AS DUFFY THREATENS MORE REDUCTIONS

“And so, we’re going to watch, analyze, encourage them to come back. But, again, we’re going to, we’re going to start to alleviate the restrictions that — we’re at 6% now — we’ll alleviate that only when the data says we should,” he added.

Thousands of flights have been canceled or delayed since cuts began on Friday. Duffy previously warned that flight cuts could go up to 20% at some airports if the shutdown continued.