Around a dozen flights have been cancelled this evening at Shannon airport due to industrial action by air traffic controllers.
The Irish Aviation Authority confirmed there will no air traffic control service at Shannon Airport tonight between 9pm and midnight.
"We regret the service interruption and inconvenience caused to our airline customers and passengers as a result of this unofficial action. Passengers should contact their airline for further information," an IAA spokeswoman said.
Management say the controllers are engaged in unofficial wildcat action but the controllers say they are only withdrawing from a voluntary overtime.
They have taken the action due to what they say is chronic under-staffing. It takes some time to train controllers even if they are qualified and the company says it has hired around 15 people who will join the service on completion of their training later this year.