"It is very unfortunate that a senior leader is making such unfounded allegations," Kejriwal told the media. "There is no truth in (what he has said)."
Gadkari, who was in charge of the BJP election campaign in Delhi, alleged earlier in the day that the Aam Aadmi Party and Congress had struck a deal to prevent a BJP government in Delhi.
This deal, he added, was also aimed at derailing the appeal of Bharatiya Janata Party's prime ministerial candidate Narendra Modi.
This information, he said, had been conveyed by a person who knew about a supposed meeting held at a five-star hotel between representatives of the AAP and the Congress.
Kejriwal Saturday took oath as the Delhi chief minister at the head of a minority government propped up by the Congress.