MSC Cruises has signed up for four "ultra-luxury" cruiseships at Fincantieri in Italy in a deal worth more than EUR 2bn ($2.3bn).
A memorandum of agreement was inked for delivery of the vessels from spring 2023 up to 2026.
The 64,000-grt units will feature 500 cabins.
MSC pledged to include the best and latest environmental technology and "other cutting-edge maritime solutions at sea".
Pierfrancesco Vago, MSC Cruises’ executive chairman, said: “It is off the back of the great success of our ship-within-a-ship luxury concept that our guests asked us to enter into the ultra-luxury segment, as a natural evolution of the MSC Yacht Club.
"These ships will be able to offer unique itineraries, thanks to their size, and the guest services will be taken to another level, including our personalised MSC Yacht Club butler service, available 24/7."
Fincantieri orderbook hits 53 cruiseships
Fincantieri CEO Giuseppe Bono added: “It is with pride that two great brands – an Italian one and one with a strong Italian DNA - well-known all over the world, today announce an important construction programme.
"MSC Cruises has recognised that our design will help them create a new generation of ships that will be cutting edge both in terms of safety and technological content, and with particular attention paid to passenger comfort."
The deal brings Fincantieri's cruiseship orderbook to 53 vessels.
In June, MSC Cruises ordered a fifth LNG-powered Meraviglia-class cruiseship in a deal with STX France.
The EUR 900m 183,500-gt vessel will be delivered in 2023 with dual-fuel engines and an advanced wastewater treatment system compliant with the world’s most stringent regulatory standards.
Its total orderbook now rises to 12 ships.
As recently as May the company said it was not planning to order more vessels.