US-based Norwegian Cruise Line has announced it will invest more than $100m to upgrade its cruise ship Norwegian Spirit.

Starting in January, 40-day modernisation work on Norwegian Spirit will take place at a dry dock in Marseille, France. The upgrade is part of the Norwegian Edge programme.

Work includes the development of 14 new venues, extra staterooms and an expanded Mandara Spa.

The project will involve adding amenities such as the main dining room, an all-day dining outlet, a 24-hour eatery, the Great Outdoors Bar and the Waves Pool Bar.

The refurbished ship will include the Spinnaker Lounge and Bliss Ultra Lounge. A new adults-only daytime lounge Spice H2O will replace the children’s waterpark.

The size of the Mandara Spa will double to almost 7,000ft². It will feature a relaxation area with heated loungers, a sauna, steam room and a new Jacuzzi room.

Norwegian Cruise Line president and CEO Andy Stuart said: “As we continue to introduce new innovative ships to our fleet, with Norwegian Encore making her debut next month, we are committed to ensuring that the experiences our guests have come to enjoy are available on even our most storied ships.

“We are excited to reinvigorate Norwegian Spirit so that she continues to provide lasting memories for guests as they sail to some of the most exotic destinations around the world.”

Following the completion of modernisation, the Norwegian Spirit will resume its service in February next year. The cruise ship will visit ten new ports of call in three continents.

In September, Norwegian Cruise Line announced a ban on single-use plastic bottles across its fleet of cruise ships, starting from 1 January 2020.