Klaus said he is looking forward to welcome the Chief Minister at the Forum's annual meeting in Davos next year.
"I am very pleased to see that Telangana has topped the 'Ease of Doing Business Reforms Ranking 2015-16' conducted by the Department of Industrial Policy and Promotion (DIPP) and the World Bank.
"This is indeed testimony to your outstanding leadership and vision for the state," Schwab said in a letter to Rao.
Telangana and Andhra Pradesh topped the Ease of Doing Business Rankings released by DIPP recently.