Sabre was this morning seeking to resolve a system issue affecting its global reservations network.
No details of the problem were immediately made available.
CBS in Dallas/Fort Worth, where the technology giant is based, quoted a Sabre spokeswoman as saying urgent efforts were being made to tackle the glitch.
The company said on its Twitter feed: “Sabre is experiencing a system issue. Our technology team is working as quickly as possible to resolve the situation.”
“Sabre systems are coming back online, and we are closely monitoring,” the company said. “We apologise for the inconvenience.”