Seventy thousand travellers with SAS will see their flights cancelled on Friday unless negotiators agree a last-minute deal to stop almost all of its around 1,500 pilots going on strike after midnight, the carrier said on Thursday.
"As a effect of the strike, domestic, European and long-haul flights have been cancelled".
In the early hours of Friday, last-minute salary negotiations between SAS and the Swedish Air Line Pilots Association broke down.
The Swedish Confederation of Transport Enterprises meanwhile said it could not accept the 13-percent wage increase demanded by the pilots, given their "already high average wage of 93,000 kronor ($9,769) a month".
SAS said it wanted to "reach an agreement to end the strike as soon as possible", but warned if the pilots' requirements were met it would have "very negative consequences" for the airline.
SAS pilots went on strike after failing to see eye-to-eye with the employer on pay and other terms of work during overnight talks that began on Wednesday and continued past an agreed settlement deadline. "In a worst case scenario, they risk having to work seven weekends in a row", the pilots' trade body said in a statement.
The airline said that negotiations in the dispute over wages had been held since March, with the support of external mediators, but that there had been a "lack of success in reaching an agreement between the parties". More than 72,000 passengers will be affected by the strike action, according to the airline.
Elsa Lundberg, 20, and Christoffer Weil, 22, had been due to travel to Scotland for a hiking trip with their college class. "But we're a big group and it's unlikely everyone would be able to get on the same flight", Lundberg said.
The airline canceled around 70 percent of its flights on Friday and Saturday.
"It's good that they're fighting for their work conditions".
Analysts at Sydbank expect the strike to cost SAS 60-80 million Swedish crowns ($6.3-$8.4 million) per day, wiping out an expected net profit for the year if it lasts for two weeks. Flights operated by SAS Ireland and SAS partner airlines will not be affected.