Saga has sold its retired ship Saga Sapphire to Turkish travel firm Anex Tour for an undisclosed sum.
The travel group will offer sailings in the eastern Mediterranean from mid 2020.
The purchase comes a week after Anex owner, Neset Kockar took a 8% stake in Thomas Cook.
Anex operates under the name Anex Tour in Russia, Ukraine, Kazakhstan and Germany and also with its Orex Travel companies in the Czech Republic, Slovakia and Poland.
The group operates 26 Boeing aircraft with three different airline companies in Russia, Ukraine, and Germany under the Azur Air brand.
Anex Tour handles about three million holidaymakers a year with operations across Europe, the Middle East, Asia and the Caribbean.
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Saga Sapphire under Anex will sail its maiden voyage from Antalya, Turkey.
The 800-passenger ship first entered service in 1982 and has operated in various guises for different cruise companies.
Saga will retire the ship in next year and introduce its second new vessel, Spirit of Adventure, in summer 2020.
Kockar said: “With changing habits of travellers, we must adopt our product offering accordingly. By acquiring Saga Sapphire, we will be able to create a unique eastern Mediterranean cruise experience for our valued guests.”
Nigel Blanks, chief operating officer Saga Cruises, said: “With her spacious cabins and comfortable public areas, Saga Sapphire has become hugely popular with our guests over the last seven years.
“As the time approaches for her to leave the Saga fleet, we are delighted that she will now have a new career launching Anex Tour’s exciting new cruise product.”