"The prospect of further industrial action cannot be ruled out at this stage," FORSA/IALPA union official Angela Kirk said in an interview with state broadcaster RTE.

Pilots in Ireland, Ryanair's home country, held a strike for the first time on Thursday as they demanded better conditions from Europe's largest low-cost carrier, which is trying to stave off a wave of industrial action across its network.

(Reporting by Conor Humphries; editing by Jason Neely)