"For three decades I have served the Congress. However, for the past 3-4 years, I feel completely sidelined," he told PTI by telephone.
"I wanted to take retirement from politics rather than leave the party, but people of the constituency (Jind) which I nursed over the years want me to move on," said 76-year-old Gupta.
The Congress leader, who last served as Transport Minister in the Bhupinder Singh Hooda government (2005-09), said he felt he was being sidelined as he was once a known follower of former Chief Minister late Bhajan Lal.
Gupta said he had consulted his supporters who were of the view that "I must leave the Congress where no place is left for me."
The veteran leader hinted at joining the Haryana Janhit Congress (BL), led by Hisar MP Kuldeep Bishnoi, at the party's rally in Sirsa on December two.
