Wartsila is launching what it claims is the first long-term trial of an ammonia-fuelled four-stroke ship engine.

The Finnish shipping technology giant will work with Norwegian LNG carrier and tanker owner Knutsen OAS Shipping and Spanish energy company Repsol on the test at Norway's Sustainable Energy Catapult Centre in Stord.

The project is being made possible by a NOK 20m ($2m) grant from the Norwegian Research Council.