Agents will be able to offer guests up to $500 of on board spending money as part of a Norwegian Cruise Line autumn promotion. The added-value offer is available on any European cruise of three nights or more departing between April 2013 and April 2014, the company said in a statement.

"Guests must be booked between 1 to 30 September 2012 to take part in the offer which includes sailings on five Norwegian Cruise Line ships. Itineraries range from Transatlantic crossings to Eastern and Western Mediterranean, Greek Isles, Canary Islands and Baltics sailings," the company said.       

Once on board, guests can redeem their on board spend against a range of experiences which could include spa treatments, speciality dining or shore excursions.