After acquiring two huge new Genesis-class cruise ships that will dwarf current cruise ships Freedom, Liberty and the soon-to-debut Independence of the Seas, Royal Caribbean is apparently planning to build a fourth Freedom-class vessel.

Aker Yards announced on March 3rd that it has signed a preliminary deal with Royal Caribbean to build the fourth Freedom-class cruise ship for delivery in the second half of 2011.

"The placement of the order is still subject to a number of conditions, including board approval and finalisation of terms and conditions," Aker Yards ASA said in a statement.

Royal Caribbean's decision to buy a fourth Freedom-class ship instead of a larger design will give the cruise line more flexibility in deployment. There currently are a rather limited number of ports that will be able to accommodate Genesis-class vessels.

The Freedom class is currently the largest cruise ship afloat at 160,000 tons and capable of carrying 3,600 guests. The Genesis class ships, first of which will debut in autumn 2009, will run 220,000 tons and carry 5,400 passengers.