"Suppose if UPA is going to form the government, my first choice will be UPA. (If) There is no scope for UPA, then we will explore the possibility of the third front," he told reporters here after a meeting of TRS office bearers and party candidates in recent elections.
Observing that separate Telangana has become a reality only because of the "initiative" of UPA chairperson Sonia Gandhi, he said he would remain grateful to her during his life time.
"I am again reiterating, if Rahul Gandhiji is going to become the Prime Minister with my support, I will be the first person to extend the support. I have regards to Smt Sonia Gandhi. I am thankful to her, I will be thankful to her in my whole life time.
"I am reiterating. I said earlier, but for the initiative of Smt Sonia Gandhi only, Telangana happened. I still believe that. I have respect for her. We have nothing against Sonia Gandhi or Rahul Gandhi," he said.
"We are not going to support NDA at all," he said.
The TRS president had called on the Congress president at her residence in Delhi, along with his family members, following the passage of Telangana Bill in parliament to thank her.
He, however, subsequently ruled out merger of TRS with Congress and even refused to have an electoral alliance with the national party.
Congress and TRS were engaged in a bitter war of words during the election campaign. Polling concluded in Telangana on April 30.
Chandrasekhar Rao expressed confidence that TRS would get absolute majority to form the first government in the new state of Telangana.