Pilots working for Ryanair have rejected the airline's proposals to forgo their holiday entitlements for bonuses.
Up to €12,000 is being offered by the airline in a bid to plug gaps in their schedule due to a backlog of staff annual leave as Ryanair moves to a calendar-year (January-December) system of annual leave.
The staff schedule issue has triggered thousands of flight cancellations around the world.
The airline expects to have refunded or processed alternative routes for 95% of affected customers by the end of this week.
Ryanair pilots across Europe are now looking for improved contracts.
They have written to Ryanair management to say they are not going to accept pay for working on their holidays, and to seek permanent contracts that include pay parity with rival airlines in their local markets.