Low cost carrier Norwegian achieved a record 12 months for carryings in a single year in 2017 with more than 33 million passengers.

A “substantial increase” in long-haul traffic contributed “considerably” to the growth as the airline added 54 routes to its overall network.

Passenger numbers grew by 3.8 million over 2016 as Norwegian’s fleet expanded with the addition of 32 aircraft and about 2,000 new staff.

The 2017 load factor was 87.5%, compared to 87.7% the previous year.

Norwegian CEO Bjørn Kjos said: “The 2017 traffic figures show that our international footprint grows stronger, in line with the Norwegian Group’s strategy.

“Our Scandinavian operation is stable and positive, and we see that our long-haul and short-haul networks complement each other, consequently strengthening our competitiveness.

“Our growing long-haul networks from the UK and Ireland continue to be well-received by passengers, proving the demand for high-quality, affordable travel. Increased tourism creates economic value and new jobs at all the destinations we serve.”

The airline’s December carryings rose by 12% year-on-year to 2.4 million with a load factor pegged at 84.6%.

Kjos said: “December has been a busy travel month in all markets we serve.

“This winter, we once again offer flights between the US east coast and the French Caribbean islands of Martinique and Guadeloupe, enabling the company to achieve better fleet utilization in low season in Europe.”

Norwegian operated 99.3% of its scheduled flights in December, of which 68.2% departed on time.