"I, very heartily, congratulate you on your winning majority in the Telangana Assembly elections and assuming office as the Chief Minister. Your wise moves and hard and sincere work have always kept you very near to the hearts of the people," Karunanidhi tweeted.
The DMK chief also recalled Rao's visits to Chennai and the discussions they had over the formation of Telangana.
"Under your able leadership, I am quite confident, the new Telangana state will enjoy a very peaceful and useful governance. I, once again, convey my good wishes to you and your party on behalf of the DMK," he said.
Chandrasekhar Rao was today sworn in as Chief Minister of newly-carved out state of Telangana.
Eleven others, including his son and nephew were also sworn in as Cabinet Ministers by Governor ESL Narasimhan, who administered them oath of office and secrecy at Raj Bhavan in Hyderabad.