United Airlines suffered a major "technology disruption" on Wednesday night, the carrier has told Newsweek via email, leading to widespread travel chaos in the United States and beyond, and it later warned of "residual delays" even though the underlying issue had been resolved.

United said it was treating the technology issue as a controllable delay, meaning it would pay customer expenses such as hotels.

United Airlines resumed operations on Wednesday night after a technology issue grounded all mainline flights, leading to over 1,000 delays.