Haryana Congress president Kumari Selja on Saturday dubbed the Jannayak Janta Party's support to the BJP in forming the new government a "betrayal" with the voters.
Selja said the 10 seats that the voters of the state gave to the JJP were a mandate against the ruling Bharatiya Janata Party.
"But the JJP betrayed the voters of the state. All those who voted for the JJP are feeling cheated today after it extended the support to the BJP," she said.
In a statement, the Congress leader said people of the state gave a befitting reply to the BJP, which was targeted to win more than 75 of the 90 seats.
"But what people of the state could not realise was that the JJP had a tacit understanding with the BJP and acted as its 'B' team," she said. "They did not take any time to extend support to the BJP as soon as the election results were out."
The BJP has staked claim to form the government in Haryana after Dushyant Chautala's JJP offered support to the saffron party, which fell short of a majority in the assembly election.
Selja said after extending support to the BJP, a question mark remained on the JJP's pre-election promises.
She pointed out to the JJP's assurances like giving an allowance of Rs 11,000 per month to the unemployed, reserving 75 per cent of the jobs for the people of the state and a monthly old-age pension of Rs 5,100.
Senior Congress leader Randeep Singh Surjewala also took a dig at JJP.
Surjewala said before the polls, the BJP used to dub Dushyant Chautala, grandson of former chief minister O P Chautala, as a person who was allegedly responsible for the family feud.
The JJP, on the other hand, used to hold the BJP responsible for "burning" Haryana, Surjewala said, referring to the violence that broke out during the 2016 Jat agitation and following the conviction of Dera Sacha Sauda chief Gurmeet Ram Rahim Singh in 2017.
"But now, the two have come together to form the government..," Surjewala tweeted.
The JJP was floated last December after a vertical split in the Indian National Lok Dal following a feud in the Chautala clan.