"Just as at present, I will take up whatever responsibility is given to me by my party in the future and do it diligently to the best of my abilities," he said in a rare interview. (Read the Dainik Bhaskar interview here)
The 43-year-old's comments come before a meeting on Friday of the top leaders in Congress where he expected to be named the PM nominee.
Mr Gandhi is No 2 in the Congress; his mother, Sonia, is the party president.
He was asked about his comment in January 2013 when he described power as "poison".
"Power is poison doesn't mean that I am not keen to take responsibility. I don't have the word 'reluctance' in my life," he said.
He also ruled out any significant role for his younger sister Priyanka, who has attended recent party meetings. "As an active Congress worker she is helping me strengthen the party. But I don't think she will have any electoral role," he said.
Though Mr Gandhi headlined the Congress campaign for the recent assembly elections in Delhi and other states, the party performed poorly, ceding massive ground to the Opposition BJP and the the upstart anti-corruption Aam Aadmi Party (AAP).
"The Aam Aadmi Party works in a different way, but I must concede that AAP has done some of the work that the Congress wished to do in Delhi," Mr Gandhi conceded.