Norwegian has signed an agreement to lease two new B787-9 Dreamliners.
The Boeing aircraft will be delivered to the airline in the first quarter of 2016.
Norwegian currently has three B787-8 Dreamliners in its long-haul fleet and a further five on order, four of which will be delivered next year and the last in 2015.
Once the two B787-9s are with Norwegian in 2016, the airline will be operating ten Dreamliners.
Norwegian CEO Bjorn Kjos said: "In order to run a competitive long-haul operation, we are dependent on brand new cost-efficient aircraft. I'm very satisfied to have secured our first two 787-9 Dreamliners.
"This is a fantastic airplane with high passenger comfort, long range and low fuel burn."
Norwegian will lease the two B787-9s from New York-based MG Aviation.
The carrier 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 Gatwick service (see news, November 29).