The Medallion will be available on the 3,560-passenger Royal Princess in April for its maiden Alaska season, followed by the 3,080-guest Crown Princess in July as the vessel sails the British Isles from Southampton.

The 3,660-guest Sky Princess, which joins the Princess fleet in October, will feature the gadget when it embarks on its maiden season in the Mediterranean before heading to the Caribbean.

As a result, all of Princess’s Caribbean-based ships will have full Medallion services from the Autumn.

Caribbean Princess and Regal Princess are already Medallion-enabled.

The Medallion, which is the same size as a 10p piece, is fully-automated and has no visible technology such as an on-off switch or charging function.

Its features include a streamlined embarkation and disembarkation process, keyless stateroom access, on-demand beverage delivery and use of an interactive direction guide, OceanCompass.

Tony Roberts, vice-president Princess Cruises UK and Europe, said: “Having recently travelled on Caribbean Princess I can say first-hand that guests are finding their holidays enhanced with Princess Medallion as a new and memorable experience.

“This will include everyone who sails with us to the Caribbean this autumn and winter.

“Starting in April, we will continue the expansion to a total of five Princess Medallion ships expected this year as we continue on our path to fleet-wide activation.

“We look forward to bringing the experience to new groups for the first time, such as those sailing to destinations in Alaska and Mexico.”