Former Chief Minister HD Kumaraswamy on Saturday challenged Congress leader Siddaramaiah to build a regional party and win at least 10 seats on his own strength before criticising JD(S) and his leadership abilities.
In a series of tweets, he also hit back at Siddaramaiah for alleging that there was an "internal understanding" between BJP and JD(S).
"I have a challenge for Siddaramaiah, who repeatedly criticises about the number of seats JD(S) could win, about Deve Gowda (JDS supremo) and me. Come out of the shelter of the national party, build a regional party and win at least 10 seats on your own strength... then speak about our leadership," he tweeted.
"...don't speak lightly about the number of seats JD(S) has won. Building an independent regional party requires leadership. You are not aware of the efforts that are required for it. It is not possible from you," he added.
Mr Kumaraswamy was reacting to Siddaramaiah's statement in Mysuru on Friday that the former could become CM as Congress agreed to give him the post despite JD(S) winning just 37 seats after the 2018 assembly polls.
The Congress leader had hit out at Kumaraswamy for the collapse of the coalition government last year, alleging that he tried to run the administration from a five star hotel and could not keep his MLAs together.
Mr Kumaraswamy alleged that Siddaramaiah had planned to bring down the coalition government months after it was formed and that most congress legislators who defected to the BJP, eventually leading to the party coming to power, were his loyalists.
On the charges of running the administration out of a five star hotel, the JD(S) leader noted that Siddaramaiah had "shamelessly" not vacated his official residence after the 2018 loss.
"Does Siddaramaiah have the moral right to speak about me..I used to work at the office till 12 in the night while he used to go to undisclosed locations after 6 pm during his tenure."
Siddaramaiah on Friday had also blamed a section within Congress for his defeat in Chamundeshwari assembly constituency in the 2018 assembly elections and asked those who had worked against the party during the polls to introspect and quit.
To this, Mr Kumaraswamy accused Siddaramaiah of having had an internal understanding with opponents to get some of his own Congress leaders defeated in some previous elections as he feared getting sidelined within the party.
"If he (Siddaramaiah) introspects rightly, he will have to quit Congress," he said.
With no party getting a clear majority in the 2018 assembly polls, Congress-JD(S) that had fought against each during the election joined hands to form a government with Mr Kumaraswamy as Chief Minister to keep the BJP out of power.
However, following the rout in Lok Sabha polls, internal differences cropped up and the rebellion by some MLAs led to collapse of the coalition government last year.
Since then Congress and JD(S) leaders have been blaming each other for it.