More than 500 flights have been cancelled due to industrial action in Italy today.
A four-hour air traffic control strike began at 1pm and was due to conclude at 5pm in addition to a dispute involving ground handlers.
Passengers were also expected to face disruption during the rest of the day when cancellations and delays will have a knock-on effect on other European flights, lobby group Airlines for Europe (A4E) warned.
Some flights could be rescheduled to avoid the strike period.
A4E managing director, Thomas Reynaert, said: “Just days after a week of disruption in France this new strike will see hundreds of thousands of European citizens and businesses taken hostage by localized industrial action, again.
“There are solutions available which would limit the impact of such strikes on travellers and business, without questioning controllers’ fundamental right to strike – we just need courageous policy-makers in Europe to help implementing them, now.
“Travellers can unite and let out their frustration about the continuous travel disruptions supporting our petition ‘Keep Europe’s Skies open’.
“We cannot let these strikes continue into the holidays and the summer break.”