US Transportation Secretary Pete Buttigieg has said he is willing to take a hard line on airlines when necessary as the Biden administration promises a radical improvement in passenger and consumer protection.

«We continue to work to make sure that the airlines meet their obligations, which we will enforce,» Buttigieg told Reuters in a wide-ranging interview on Thursday.

US airlines have sparred with the administration in recent years over liability for flight delayspassenger rights, landing slots and other matters. Carriers and a federal audit say the Federal Aviation Administration air traffic control staffing should be increased.

Buttigieg has opened numerous investigations and imposed fines for carrier misbehavior. President Joe Biden has often been critical of airlines, saying in February “airlines cannot treat your child as a piece of luggage.”

While Buttigieg works with airlines when possible, he added: «We’ll beat the crap out of them when we think it’s important for passengers to get a better deal.»

Buttigieg said he is “in the middle of what I intend to be the biggest expansion of passenger rights in years. And there are tensions that will naturally arise with that.»

United Airlines CEO Scott Kirby recently suggested that the Federal Aviation Administration had «failed us» before changing his tune.

In late June and early July, United had a higher number of cancellations which it attributed in part to air traffic control staffing issues.

“It was another scenario where it seemed like the rest of the system was recovering and a player was struggling, so certainly something we’re looking at,” Buttigieg said.

By the end of 2022, Southwest Airlines (LUV.N) suffered a operational merger after bad weather that also affected his companions was exacerbated by his legacy scheduling system. Buttigieg has an ongoing investigation into the Southwest collapse, but declined to discuss the findings.

Buttigieg said the US airline industry has improved over the past year, citing lower cancellation rates and adding that «schedules are more realistic, certainly the results are better.»

The Department of Transportation plans to propose new rules requiring airlines compensate passengers for significant flight delays or cancellations where carriers are liable.

Buttigieg said the July 1 launch of 5G C-Band has gone better than expected with minimal disruption. Last month, warned of possible delays for aircraft without up-to-date radio altimeters.

Buttigieg said airlines were largely prepared, but that “took a lot of pressure. He took several moments where we really had to make sure they could read our body language that we really meant business… I don’t think the airlines bought us from the start.»

The FAA has been without a Senate-confirmed administrator since April 2022 and a the previous candidate withdrew in March.

Buttigieg said the White House was close to naming a new nominee. The White House has been considering naming former FAA deputy administrator Michael Whitaker, sources told Reuters, but Buttigieg declined to identify the expected candidate.