Jyotiraditya Scindia was speaking at a campaign rally for the Madhya Pradesh by-elections.
Competing for the shrillest elections in recent memory, the Madhya Pradesh by-polls inducted a new contender on Saturday with BJP MP Jyotiraditya Scindia claiming that former Chief Minister Kamal Nath, already censured for calling a female politician an "item", has now called him a "dog".
"Kamal Nath ji came here to Ashoknagar and called me a dog. Haan, Kamal Nath ji, main kutta hoon (Yes, I am a dog) because the public is my master. Yes, I am a dog, because a dog protects its master," Mr Scindia addressed his former Congress colleague at a campaign rally.
The Congress quickly denied the allegation, with a spokesperson for Mr Nath telling news agency PTI that the former chief minister never used such a word for Mr Scindia or any other leader. "Kamal Nath never used this word for anybody in his speeches," Narendra Saluja said.
However, shortly after Mr Scindia's clip went viral, another video emerged of Congress's Acharya Pramod Krishnam speaking earlier at a rally in the same area, saying, "When Kamal Nath ji was trying to act against a mafia don here, someone protected him like a faithful dog." He did not name Mr Scindia.
Earlier in day, Kamal Nath took the Election Commission to court after it revoked his privileges as a "star campaigner" for a series of controversial remarks by the Congress leader including calling a BJP's Imarti Devi an "item".
Later, he had also said at a rally that Chief Minister Shivraj Singh Chouhan is a "nautanki kalakar who should act in films in Mumbai". He said: "Aapke Bhagwan toh woh maafia hai jisse aapne Madhya Pradesh ki pehchaan banai. Aapke bhagwan toh milawat-khor hain (Your god is mafia - an apparent attack on the chief minister)."
By-elections are being held on November 3 to fill 28 vacant seats in the Madhya Pradesh assembly. Most of these fell vacant when Congress leader Jyotiraditya Scindia revolted earlier this year and defected to the BJP, taking along 22 MLAs.
Kamal Nath's Congress-led government fell and the BJP returned to power. The BJP needs to win at least eight of these seats to stay in power. If at all the Congress manages to win all 28, it can make a comeback attempt.
On the campaign trail, the Congress has been ranged against its own, with Kamal Nath lashing out at former party men who are now contesting as BJP candidates.