or: rgb(51, 51, 51); font-family: Lato, Helvetica, Arial, sans-serif; font-size: 16px;">Seabourn is to enter the expedition market after signing a letter of intent with shipbuilders T.Mariotti and Damen.

The line has announced it will launch two luxury expedition ships, with the first delivery coming in June 2021.

The second is ship is expected to launch in May 2022.

Both 264-passenger capacity ships will have two submarines on board and will be designed to carry a complement of kayaks and 24 Zodiac inflatable boats.

The 170 metre, 23,000 gross ton vessels will add new capacity for Seabourn in Antarctica, the Arctic and other destinations around the world.

Richard Meadows, Seabourn’s president, said called the announcement “groundbreaking” for both the line and luxury travellers.

He said: “The combination of immersive experience, fine accommodations and sumptuous amenities offered by these new ships builds on the success of our current product and further demonstrates our leadership as innovator.”

Seabourn will announce design and service details for the new ships later this year.

Itinerary details and booking availability will be released early next year.

The first ship will sail in the Arctic in late summer 2021 before sailing itineraries in Antarctica during the fol