American Airlines said Friday it had resumed operations following problems related to a major worldwide computer systems outage.

“Earlier this morning, a technical issue with a vendor impacted multiple carriers, including American. As of 5:00 a.m. ET (0900 GMT), we have been able to safely re-establish our operation,” it said in a post on social platform X.

A major IT outage has wrought havoc on computer systems worldwide, grounding flights across the globe, including in Europe and the United States, derailing television broadcasts in the UK and impacting telecommunications in Australia.

US carriers Delta and United Airlines grounded all their flights earlier Friday over communication issues, the Federal Aviation Administration (FAA) said.

The FAA said later it was “closely monitoring a technical issue impacting IT systems at U.S. airlines.”

It said several US airlines had requested its “assistance with ground stops for their fleets until the issue is resolved.”