Mr Darkins leaves his post after more than 30 years in the real estate industry and 17 years with TH Real Estate, the company said in a statement.
Mr Darkins led the expansion of parent company Henderson’s real estate business throughout Europe and Asia Pacific, leading to the formation of TH Real Estate in 2014, the statement said.
Mr Sales, who is currently managing director, will take over as head of TH Real Estate starting in September, the company said. He has worked in the real estate industry for more than 25 years and spent 21 of those years with TH Real Estate and its predecessor company.
Mr Darkins will continue his role as chief executive until the end of August and will remain with the business until the end of year to ensure a smooth transition to Mr Sales.