Ryanair has said around a quarter of flights operating from Germany were delayed this morning amid a pilots' strike in the country.
However, the airline says no flights were cancelled.
Pilots walked off the job between 5am and 9am, following the breakdown of talks between unions and management in Germany.
The union decided to proceed with the industrial action after it said talks ended without agreement.
It called on management to take part in "constructive negotiations", and apologised to all affected passengers, cabin crew and ground crew.
In a statement, Ryanair said: “9 of our 36 first wave flights operating from Germany this morning were delayed, but there have been no cancellations, and Ryanair expects to operate all of our German scheduled flights today. We are grateful to all of our Ryanair pilots for putting our customers first and largely ignoring this VC strike.
"We apologise sincerely to our customers for any inconvenience suffered as a result of this unjustified and unnecessary strike by a small number of pilots organised by the Lufthansa (VC) pilots union."
Here, the strike threat receded yesterday after the company wrote to IMPACT confirming union recognition.
Pilots in Ireland had initially planned a work stoppage on Wednesday December 20th.
In a bid to avert the pre-Christmas action, Ryanair broke from its long-standing policy of not recognising unions, and met union leaders for the first time in the company's history earlier this week.