The €670 million (£575 million) deal will see Riu take full ownership of 19 properties jointly-owned with Tui, and a further two under development.
Peter Krueger, chief strategy and M&M officer for Tui Group’s hotel investments, said the deal would separate hotel management and holiday experience from ownership.
The management of all 100 Riu hotel and resorts worldwide will continue under a 50-50 joint venture between the two firms, including the 21 properties Riu is set to take full ownership of.