Pilots working for Ryanair have rejected the airlines 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.
The staff schedule 'mess up' has triggered thousands of flight cancellations around the world.
The airline expects to have refunded or processed alternative routes for 95 percent of affected customers by the end of this week.
Business Journalist with the Irish Independent, John Mulligan, says pilots are also looking for improved contracts:
“We now have a situation where Ryanair pilots from bases all over Europe have written to management and said we are not going to give up our holidays,” he said.
“We are not going to take pay to work over our holidays and that is going to create a major headache for Ryanair in terms of trying to fill its schedule.”