"All India Congress Committee has approved the proposal sent by Karnataka Pradesh Congress Committee to take action against R Roshan Baig, MLA on account of his anti-party activities," the state Congress said in a release.
"He has been suspended from the party with immediate effect, on the basis of inquiry conducted on this matter," it said.
Hitting out at Congress leaders for the party's performance in the Lok Sabha polls, Baig, a MLA from Shivajinagar, had recently held Siddaramaiah's "arrogance" and KPCC president Dinesh Gundu Rao's "immaturity" responsible for the "flop show."
He also called AICC general secretary K C Venugopal a "buffoon."
He had also dropped hints of quitting the party, and appealed to Muslims to "compromise" with the situation, on National Democratic Alliance returning to power.
The Karnataka PCC had issued a show cause notice to Baig for his conduct, to which he has not responded, according to sources.
Earlier in the day, KPCC president Dinesh Gundu Rao had said Baig's alleged links with IMA jewels involved in an alleged financial fraud, duping thousands of investors, would be brought to the notice of central leadership for further action.
Revenue minister R V Deshpande Monday said Baig had introduced the firm's owner Mohammed Mansoor Khan to him about two months ago but denied doing any undue favour.
Baig, a seven-time MLA and a former minister, has been expressing displeasure against the Congress party leadership on not being included in the coalition cabinet headed by H D Kumaraswamy.
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