Royal Caribbean Cruises has exercised an option to build a second Sunshine-class cruise ship to be delivered in spring 2015.
The ship will be built by German shipbuilder Meyer Werft on substantially the same terms as the first Sunshine ship, the company said.
Chairman and chief executive Richard Fain said: “This confirms our continued confidence in the success of this new generation of ships and our strong conviction about the Royal Caribbean International brand.”
The line signed a letter of intent for the two ships 12 months ago, with the first due to enter service in the autumn of 2014.
The 158,000 tonne vessels will be larger than Royal Caribbean’s Freedom-class series of three 3,600-passenger ships.