(9:15 a.m. BST) -- The parent company of Marella Cruises, TUI, has purchased three river cruise ships with itineraries in place for mainland Europe from summer 2020.

TUI River Cruises -- on sale on April 25 with 19 itineraries available on the Danube, Rhine, Moselle and Main rivers -- has purchased three ships from two operators, Werner-Tours and Reiseburo Mittelthurgau Fluss. The ships will continue to sail for their former owners until October 2019.

The fleet of three adults-only ships will feature a selection of balcony suites, a la carte dining, casual dining and social venues onboard.

Direct flights from UK airports, airport transfers to and from the ship, 1GB of Wi-Fi per cabin, per week, tips and port charges and £120 credit towards shore excursions will be included in the fare.

Passengers will have the option to select their board basis, including full-board plus, including wine, beer and soft drinks with meals, or full board with the add-on of a premium drinks package. Deck barbecues (weather permitting) and nightly entertainment will also feature on the ship's onboard programme.

Chris Hackney, Managing Director of Cruise for TUI UK & Ireland said: "We’re incredibly excited to be moving into the river cruise market, we’re always looking for new opportunities to offer our customers even more variety when it comes to choosing the perfect holiday and our river cruises will really take this to the next level as customers are able to personalise their package whether that’s board type, cabins, excursions and even cocktail choice.

"We're very proud to be known for the friendliest service, exciting itineraries and great value for money when it comes to our ocean cruises and we look forward to bringing this to TUI River Cruises."

Itineraries will include a 14-night "European Icons" cruise from Amsterdam to Budapest.