Scandinavian airline SAS has cancelled hundreds of flights scheduled for tomorrow as a pilot strike entered its second day, disrupting the travel plans of tens of thousands of passengers.

SAS pilots went on strike yesterday as wage talks broke down, grounding around 70% of the airline's flights and hitting some 170,000 people over the weekend alone.

"We deeply regret that our customers are affected by the ongoing pilot strike," SAS said in a statement, outlining its flight cancellations for the rest of the weekend.

"Due to the strike another estimated 64,000 passengers will be affected when 587 flights are cancelled across Scandinavia."

SAS has taken steps such as offering free food to passengers waiting to find alternative flights at airports across Scandinavia, but several travellers complained on social media that they were unable to reach the airline's customer services.

"Hey SAS I've been trying to contact you for a day now," one wrote on Twitter, to which SAS responded: "Our customer service is answering the phone as fast as they can. Try again".

The flag carrier, which is part-owned by the Swedish and Danish governments, has said it is prepared to resume negotiations but warned that meeting pilots' demands would have dire consequences for the company.

The aviation industry's employer body in Sweden has said pilots demanded a 13% wage hike, despite what it called already high average wages of 93,000 Swedish crowns (€8,700) a month.

The SAS Pilot Group, a union body representing 95% of the airline's pilots in Denmark, Norway and Sweden, says that the dispute concerns more than simply wages, pointing to demands for more predictable and transparent working hours.

Analysts at Sydbank have estimated that the strike is costing SAS €5.6-7.5m per day, which would effectively wipe out the airline's expected net profit for the year were it to last two weeks.

The strike at SAS does not affect flights operated by its partners, which make up roughly 30% of all departures.The airline said it was offering passengers booked on flights through 1 May to reschedule free of charge.