The announcements were made during the Horizons: D23 Disney Experiences Showcase at the weekend (15 August) as DCL pursues its plan to expand its fleet to 13 ships by 2030.
The first ship in the new class, plans for which currently comprise three ships in total, will enter service in 2029 aiming to occupy a new "sweet spot" size category for the brand.
Larger than Disney Magic and Disney Wonder but smaller than its new newer Wish-class vessels, DCL said the ships are designed to give Disney "greater flexibility to explore new destinations and reach new markets".
Further details of the ships and their itineraries are yet to be revealed.
Meanwhile, Disney Cruise Line has shared further details of Disney Believe, its fourth Wish-class ship, which is scheduled to enter service in late 2027.
The ship's Grand Hall will be themed around the "optimistic spirit" of Moana, with a bronze statue of Moana, Pua and Heihei forming its centrepiece.
The line's fourth Wish-class ship will also feature colourful exterior artwork
The ship will also feature colourful exterior artwork, including Woody and Buzz Lightyear on the stern, where the Toy Story characters will appear to be drawing the ship's name in yellow crayon.
At the bow, a hand-painted filigree depicting Tinker Bell, Peter Pan, Wendy and Captain Hook will reference the 1953 animated classic.
Disney Believe will feature new venues and entertainment inspired by Disney stories including Encanto, Frozen, Snow White and the Seven Dwarfs, Moana and The Little Mermaid.