Siddaramaiah, who held the post of Deputy Chief Minister in the Congress-JD(S) coalition government then, was subsequently ousted from the JD(S) and also as its legislature party leader. He later joined the Congress.
Former prime minister Deve Gowda on Saturday termed Karnataka Chief Minister Siddaramaiah as "mean", and said grooming him was his "biggest mistake".
"He (Siddaramaiah) is a mean Chief Minister," Gowda said while complaining that he was not given an opportunity to speak during the inauguration of Mahamastakabhisheka of Lord Gommateshwara Bahubali at Shravanabelagola on February 7, which was attended by President Ram Nath Kovind.
Stating that his name was printed on the invitation as former Prime Minister and Chief Minister and as Lok Sabha member and speaker at the event for "namesake", he said "but I had no chance to speak. The Chief Minister who is mean to this extent, has grown from this party (JD(S))."
"Is he a Chief Minister? How long will you stay? I will see. I have taken a vow. I will today seek apology from the people of Karnataka for grooming such an immoral politician," he said.
"Grooming such a lowly Chief Minister is my biggest mistake. I will repeatedly say he is unfit to continue in the post," a visibly upset Gowda remarked at a party event.
Relations between Gowda and his one-time trusted aide Siddaramaiah came under strain in 2005 as the latter was unhappy over party affairs and dominance of the former Prime Minister's son H D Kumaraswamy, the then JD(S) state unit working president.
The issue of alleged "ill-treatment" meted out to Gowda during the Mahamastakabhisheka had also resonated in the Assembly last week, when his son and JD(S) MLA H D Revanna moved a privilege notice accusing that he too was "ill-treated" at the programme at the behest of the minister in charge of the district.
The privilege notice has been referred to the privileges committee by the Deputy Speaker.