"Despite repeated attempts by management to engage in constructive discussions to prevent a hardening of the strike, dialogue was was not possible," the Norwegian airline said in a statement on Tuesday night.
"This unfortunately leads to the cancellation of all domestic flights in Norway, Sweden and Denmark tomorrow, Wednesday, March 4th. All departures between Scandinavian capitals are also canceled."
As many as 700 of Norwegian's pilots are set to go on strike on Wednesday, as all the company's Norwegian and Swedish pilots join the strike that began on Saturday, following more than three months of fruitless negotiations over pay and conditions.
The airline on Tuesday said it would also send as many as 800 cabin staff home without pay as it institutes its threatened lockout of workers.
"It goes without saying that if the pilots are not going to work, we have to lay off the crew," press spokesman Lasse Sandakerveien-Nielsen said. "There is talk of up to 800."
Delays and cancellations have affected a small number of flights in Norway and internationally since 70 pilots from the company's Norway subsidiary went on strike on Saturday.
As well as its flights in Scandinavia, eleven international flights to Germany, The Netherlands, Poland, the United Kingdom, Spain, and Latvia, had also been cancelled by Wednesday morning, according to Norway's VG newspaper.
Pilots based in Finland and Spain could be brought in if the strike expands, Norwegian has said.
On Monday the company’s board held a six-hour emergency meeting, but, contrary to media reports on Sunday night, the board did not use the meeting to declare its Norwegian subsidiary bankrupt.
Norwegian is Scandinavia’s third-largest airline and has around 4,500 employees. Its parent company Norwegian Air Shuttle (NAS) is partly owned by subsidiaries in Sweden, Denmark, Finland, Ireland and Singapore.
The company has set up a phone number in Norway where passengers whose flights have been cancelled can rebook tickets and request refunds.