Ryanair pilots in Belgium, Sweden and Ireland are set to stage a 24-hour strike on Friday and pilots in Germany and the Netherlands could join in too.
A poll by the Association of Dutch Pilots (VNV) found 99.5% would be in favour of a strike while Vereinigung Cockpit (VC), the German pilots’ union, said 96% of Ryanair pilots voted in favour.
Talks are ongoing in both countries.
"Ryanair has been playing for time in the negotiations since January," said a VC statement.
"If the signal given by this vote is not taken seriously, then strikes – such as in other European countries – are inevitable."
The confirmed action on Friday by pilots in Belgium, Sweden and Ireland will lead to the cancellation of 146 flights – 104 to and from Belgium, 22 in Sweden and 20 in Ireland – and will impact 25,000 passengers.
Ryanair has described the strikes as unnecessary and said it will re-accommodate or refund all passengers who are affected.
"We apologise to our customers for the disruption these unnecessary strikes will cause," said Ryanair.
