HAMILTON, Canada

Transportation Secretary Sean Duffy said Friday that US flights could face reductions of up to 20% if the government shutdown continues, as the initial reduction of 10% in flights will be implemented over the coming week.

"We are going to implement a 10% reduction in flights over the course of the next week. And again, that is from the data that we see from our safety team at the FAA (Federal Aviation Administration)," Duffy told Fox News.

Noting that staffing issues are a key driver of delays, he said: "What that means is air traffic controllers are calling in sick. That happens in different parts of the country. As that happens, you'll also see additional delays throughout the American airspace."

Duffy blamed the government shutdown for worsening staffing shortages, as he argued that “the problem we really have is air traffic controllers aren't being paid, and they're being forced to take secondary jobs again, whether it's waiting tables or driving Uber instead of coming to towers and doing their day jobs."

He warned of escalating capacity cuts."If this shutdown doesn't end relatively soon, the consequence of that is going to be more controllers don't come to work. And then we're going to have to continue to assess the pressure in the airspace and make decisions that may, again, move us from 10% to 15% maybe to 20."

Urging Congress to resolve the shutdown quickly, he said: "Let's end the shutdown, and let Congress debate their issues. But let's not hold the American people hostage and air travelers hostage by the shutdown that's gone on to a historic level right now."

Even if the government reopens immediately, Duffy noted that it could take days for controllers to return and airlines to restore full flight schedules.

"It can be, you know, days, if not a week, before we get back to full force flights, when the shutdown ends," he said.

The shutdown, which began Oct. 1, has halted pay for federal employees, including air traffic controllers and Transportation Security Administration (TSA) officers, who remain on duty without pay.

The shutdown became the longest in US history, hitting 38 days Friday, with no resolution in sight as Republicans and Democrats in the Senate remain deadlocked on restoring funding to closed federal agencies.

It surpassed the previous record of 35 days set during Trump’s first term between December 2018 and January 2019 after the upper chamber rejected a House-passed Republican funding bill for a 14th time to end the shutdown Tuesday.