Italian carrier ITA Airways has cancelled at least 200 international and domestic flights due to a nationwide 24-hour strike.
Other flights face disruption due to the national strike in Italy on Friday (October 21), EasyJet has warned.
The industrial action will affect air traffic control and airport ground handling services.
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EasyJet said: “Like most airlines operating to and from Italy, we may see some disruption to our flying programme on this date.
“We advise customers travelling to, from or within Italy on Friday 21st October to allow additional time to travel to and from the airport and to check the status of their flights.
“Should any flights be cancelled then we will contact customers via email and SMS using the details provided at the time of booking and check in.
“For cancelled flights only, we advise customers not to travel to the airport but to transfer their flights free of charge or take a refund.”
The airline added: “Although this is outside of our control, we would like to reassure customers that we are doing all we can to minimise any disruption that may occur as a result of the strike action.”