"We have set a deadline for midnight on Sunday," Hans-Erik Skjæggerud, head of the Parat union, told The Local. "If we don't meet an agreement by then, there will be strike action."
The strike is expected to ground flights in Oslo, Stavanger, Bergen, Trondheim, Stockholm Arlanda and Copenhagen.
"Of course we hope that the strike will be as short as possible. That's why we've decided take out all of our pilot members on the first day, so that the strike will be as effective as possible."
Skjæggerud said that the union feared that Norwegian's new corporate structure was intended to divide pilots between different national subsidiaries, ending the existing collective bargaining agreement.
"We're talking about the pilots working for Norwegian in Norway, Sweden and Denmark. We have for many years had a collective agreement for all these pilots. But Norwegian's opinion now is that there cannot in the future be one collective agreement applying to all the pilots."