Norwegian will open a new base of operations in Barcelona in the spring that will enable it to launch four new routes and increase the frequency on its London Gatwick service.
The new routes will begin in early April and will be from Barcelona to Sandefjord Torp, Hamburg, Berlin and Warsaw.
From March 31, Norwegian's Barcelona to Gatwick flights will operate daily, up from the current three weekly services on Tuesdays, Thursdays and Sundays.
Its Barcelona to Helsinki route will also turn daily, while it will operate 13 weekly flights between the Spanish city and Stockholm.
Norwegian will have three new Boeing 737-800s based at Barcelona-El Prat Airport.
Bjorn Kjos, the carrier's CEO, said: "We have decided to open a new base in Barcelona to meet the demand for non-stop flights to and from Spain's second largest city and the capital of Catalonia.
"It is strategically important for us to establish a base in Barcelona, as we are considering the airport for future long-haul operations."
Barcelona is Norwegian's sixth base in Spain, following ones in Madrid, Alicante, Malaga, Las Palmas and Tenerife.
Earlier this month, IAG chief executive Willie Walsh dismissed Norwegian's new low-fare transatlantic service between Gatwick and the US as "not significant" (see news, November 1).