Around 360 flights have been cancelled with over 4,000 passengers involved, a spokesperson for the UIL Trasporti union said on Wednesday.

Unions FILT-CGIL and UIL Trasporti called a four-hour strike starting from 0800 GMT for Ryanair workers in Italy, complaining about a cut in pay linked to on-board sales and tough labour conditions at Europe's biggest budget airline.

Pilots and flight attendants of easyJet were also striking from 1100 to 1500 GMT.

To cope with another strike called by ENAV flight controllers on Wednesday, Italy's ITA Airways has re-routed approximately 99% of its passengers, the airline said in a statement.

Passengers across Europe have faced delays and cancellations over the past week as airlines and airports struggle to cope with a rebound in travel at the start of the summer season.

Ryanair ranked first for the number of passengers travelling to and from Italy last year as Alitalia shrunk its network before handing over to smaller ITA Airways.

(Reporting by Sabina Suzzi, Editing by Louise Heavens)