Ryanair cabin crews in Spain, Portugal, Italy and Belgium have announced plans to strike later this month.
Crews in all four countries will strike for 24 hours on July 25th.
Crews in Portugal, Spain and Belgium, meanwhile, will hold a further 24-hour strike on July 26th.
Unions say they are taking the action after Ryanair refused to meet a deadline for a series of demands over employment conditions.
Meanwhile, Ryanair pilots based in Dublin say they have seen no evidence whatsoever that management are willing to engage in meaningful negotiations with them.
A ballot of around 100 pilots directly employed by the airline led to a strike being called for next Thursday.
Picture by: Niall Carson/PA Wire/PA Images
Intending passengers have yet to find out if the strike will go ahead next week.
In a statement by parent union Fórsa, the pilots say they've always been willing to meet with Ryanair, but they say management have no intention of negotiating on what they say are reasonable requirements.
In a statement to the airline, the union said: “We have consistently suggested a neutral venue which we will pay for and it is beyond anyone’s understanding why you will not simply agree to this.
"It is yet another example of a Ryanair view which is 'it’s either our way or no way'".