Madkaikar submitted his resignation from the Congress, as well as legislator from Cumbharjua assembly constituency, before formally joining the Bharatiya Janata Party at the ruling party's state headquarters in presence of Defence Minister Manohar Parrikar, Chief Minister Laxmikant Parsekar and state BJP President Vinay Tendulkar.
"I made a mistake by quitting the BJP and for the last 12 years I was repenting it," Madkaikar said.
Madkaikar is the second Congress MLA to to join the BJP, after Cortalim legislator Mauvin Godinho.
With their quitting, the legislative strength of the Congress from nine to six as Taleigao legislator Atanasio Monserrate was expelled from the party more than a year ago for anti-party activity.
Incidentally, Parrikar, when he was Chief Minister, had accused Madkaikar of making attempts to grab land and of corruption, during a discussion in the assembly and had even ordered a police probe into the affair.
Asked if he continues to back the allegations made against Madkaikar, Parrikar said: "An enquiry is being conducted. We will have to find out the status of the enquiry".
He also said that if the enquiry brings up something adverse, "action will be taken".