The airport earlier urged passengers to contact their airline for the latest flight information.
The outage caused some incoming flights to be diverted.
“Due to an IT issue with our air traffic control provider, no flights are currently operating. Teams are working on the issue and will resolve as soon as possible,” the airport said.
It didn’t disclose any further details about the outage or what caused it.
Flights have now resumed, initially with some cancellations and delays to destinations including to London, Amsterdam and Frankfurt.
Flights were grounded for little more than an hour before the airport announced the issue was fixed, although some departing passengers said they were stuck on the tarmac for more than two hours.