Finnair on Sunday said it was cancelling 143 flights on Tuesday, impacting some 6,500 passengers.
The flight cancellations are the result of industrial action by the Finnish Aviation Union (IAU), scheduled to take place on Tuesday at Helsinki Airport.
There's a chance baggage handling will face disruptions at Helsinki Airport on Tuesday. That said, Finnair is advising passengers travelling on Tuesday, 17 June, to check in ahead of time, arrive at the airport well ahead of departure, and pack essential items, such as medications, in their carry-on luggage.
Finnair had previously announced that it would cancel the majority of its flights on Tuesday and Thursday of Midsummer week if the industrial action by the IAU goes ahead.
The airline said it will inform its customers about possible flight cancellations for Thursday on Tuesday.
Finnair previously noted receiving an "avalanche of feedback" from disgruntled customers as walkouts by workers have led to the cancellation of hundreds of flights throughout the spring.
The large-scale cancellation of flights by Finnair due to the union's walkouts has affected an estimated 200,000 passengers — and led to an unprecedented level of contacts with the airline's customer service department.