Adam Goldstein, chief executive of Royal Caribbean Cruises’ flagship subsidiary, says the line will add 75 staterooms to the 3,114-berth vessels over the next few years.

The ships will also receive new “culinary, entertainment and technology features”, he said during a conference call with analysts.

The vessels, which represent 25% of the brand’s capacity, were delivered from what is now STX Finland in Turku between 1999 and 2003.