A total of 1,409 Scandinavian Airlines (SAS) pilots from Sweden, Norway and Denmark went on strike on Friday, causing 673 cancellations so far and over 70,000 passengers affected.
SAS warned that the continuing strike could affect a further 100,000 passengers over the weekend, reports Xinhua news agency.
In the early hours of Friday, last-minute salary negotiations between SAS and the Swedish Air Line Pilots Association broke down. As a result, 492 Swedish SAS pilots went on strike, followed by 545 Norwegian and 372 Danish colleagues.
"It is deeply regretful that the pilots strike will have a negative impact on our customers. SAS is prepared to continue to negotiate, but if the requirements were to be met, they would have very negative consequences for the company," SAS Director of Communications Karin Nyman said.
SAS is the leading airline in Scandinavia, operating a third of all flights to and from the region. According to SAS, about 70 percent of the company's flights are affected. Flights operated by SAS Ireland and SAS partner airlines will not be affected.
Friday's strike follows unsuccessful salary negotiations between SAS pilots and their employer.
According to media reports, an 11th-hour bid offered on Thursday night included a salary increase of 2.2-2.3 percent, significantly lower than the 13 percent the pilots' union is demanding.
SAS has offered passengers traveling on Friday, Saturday, Sunday and Monday the opportunity to re book their journey free of charge.
It's unclear how long the strike will last, so passengers traveling in late April and early May are advised to check for updates on the situation.