The White House says the Federal Aviation Administration is "working aggressively to get to the bottom of the root causes of what happened with the system outage" earlier Wednesday and "making sure that it doesn't happen again."
Watch the briefing in the player above.
Thousands of flights across the U.S. were canceled or delayed after a government system that offers safety and other information to pilots broke down, stranding some planes on the ground for hours.
The White House said there was no evidence that a cyberattack triggered the outage, which upended travel plans for millions of passengers. President Joe Biden said he directed the Department of Transportation to investigate.
The breakdown showed how much American air travel depends on an antiquated computer system that generates alerts called NOTAMs — or Notice to Air Missions — to pilots and others.
Speaking at the White House briefing, press secretary Karine Jean-Pierre said, "the safety of Americans who are flying every day is a number one priority. And what they're going to do is to make sure that this doesn't happen again."
The press secretary also addressed First Lady Jill Biden's surgery Wednesday to remove a potentially cancerous lesion above her right eye.
The first lady and President Joe Biden remained at Walter Reed National Military Medical Center in Bethesda, Maryland, as of midafternoon.
Asked what business President Biden was able to conduct from Walter Reed, Jean-Pierre responded, "today is about his wife. That is the focus for the president right now."
"This is about the president supporting his wife of 45 years," she said.