The retained consumer and corporate brief tasks the agency with raising awareness of the apartments among investors and the hotel among potential visitors.
FTI is understood to have beaten a rival agency to the work for Dalian Wanda, which is China’s largest property company.
One Nine Elms is Dalian’s first venture in the UK and Wanda Vista will also be the first five-star hotel to be opened by a Chinese owner outside China.
The complex consists of two towers, of which the higher will be 200 metres, and will be located at the eastern end of the Nine Elms district between Battersea Park and Vauxhall.
The formerly industrial area on the south bank of the Thames is set to undergo extensive redevelopment, including projects such as the US Embassy, which will be located half a mile from the hotel.
Dalian acquired the One Nine Elms project from an Irish developer, Green Property, in November. It received final planning permission in May, when London Mayor Boris Johnson was criticised for allowing Dalian to drop 10,000 square metres of office space from the plans.
FTI will report to Wanda One sales and marketing director Michelle van Vuuren, who said: "FTI’s deep experience and knowledge of property and London, combined with expertise on China, adds considerable gravitas to the One Nine Elms project team."
The agency’s team comprises Sue Brown, Giles Barrie and Ollie Pratt in the real estate practice and George Hudson, who is also a China specialist, in the leisure/consumer practice.