Spanish air traffic controllers are threatening strike action ahead of the summer peak flying season in a dispute of irregular working patterns.
Airports on the east coast of Spain and the Balearics, including at El Prat in Barcelona, Palma, Ibiza and Menorca could be affected.
A representative from an assembly representing workers told The Sun that unless their demands were met, some could leave their posts from the end of this week.
Raul Tobaruela revealed that he was not optimistic that an agreement would be reached as the group were currently being ignored by the new Spanish government and ENAIRE, the air traffic service control provider.
Workers are demanding more than one day off out of every eight so they can spend more time with the families.
They are also asking for a more consistent rota as they complain that currently they are often scheduled to work an exhausting pattern of nights and mornings.
Staff claim the irregular pattern of work can lead to workers becoming fatigued, which could prove deadly given the high-pressure nature of their job.
“Our conditions are far from being normal,” Tobaruela reportedly said.
“I can assure you that our working situation is the worst in the entire of Europe.
“We would not anticipate too many flights being cancelled but there could be huge delays because there will be staff shortages.”