Carlson has taken a majority stake in Stockholm-listed Rezidor, increasing its holding from 44.4% to 50.1%.
The move signals the US company's intent on having control over its brands as it seeks to grow to 1,500 hotels by 2015.
To an extent there has been a reverse takeover by Rezidor of Carlson's hotel operations as senior executives have moved across from Brussels to Minneapolis. Particularly telling was the announcement this month of the first US property for the Radisson Blu brand, a brand developed in Europe in response to the perceived quality differences between the US and European Radissons.
Thorsten Kirschke, COO of Carlson Hotels in the Americas and one of the Rezidor implants, said the $125m US Radisson Blu in Chicago was "part of the moves we are making to align our US brand with our global standards".
Rezidor meanwhile is continuing to grow at a rapid pace and last month took over management of the biggest hotel chain in the Baltics. The deal with the 10 Reval hotels was struck with Norwegian developer Linstow. The move adds 2,367 rooms with six hotels becoming Radisson Blu and four Park Inn.
"After developing and building up the Reval Hotels chain in the Baltics, Linstow now wishes to focus on its core role as a real estate developer and real estate investor," said Linstow CEO Per Mortensen.
Last month Rezidor said revpar across its estate was down 0.1% with occupancy rising to 56.3% from 53.2%. It signed eight new contracts for hotels representing 1,500 rooms.