Following a major air travel crisis which grounded thousands of flights, the American government on 11 January 2023 said that there was no evidence of a cyber-attack.
A technical failure in a system which alerts pilots had led USA's Federal Aviation Administration (FAA) to order grounding of flights.
The White House said that President Joe Biden has asked the Department of Transportation to conduct a full investigation, and provide regular updates.
More than 9,500 flights were delayed, and more than 1,300 were cancelled, according to FlightAware, a plane tracking company.
Also watch: US air services resume after system outage grounded thousands of flights
"This is incredibly important, a top priority, the safety of Americans who are flying every day," White House Press Secretary Karine Jean-Pierre told reporters at her daily news conference.
"We want to make sure that they're safe. This is a top priority for the President, top priority for the Department of Transportation and certainly the FAA. And so, we want to make sure that we get to the root causes so this does not happen again," she said.
(With agency inputs)