Kapil Mishra, a former minister in Arvind Kejriwal's government, announced on Friday that he will be joining the BJP.
Delhi Assembly Speaker Ram Niwas Goel earlier this month had disqualified Kapil Mishra under the anti-defection law after he campaigned for the BJP during Lok Sabha elections in May.
"I am joining BJP tomorrow at 11 a.m.," Mr Mishra said in a tweet.
Top Delhi BJP leaders confirmed that Mr Mishra, once a close aide of Mr Kejriwal, will be joining the party.
A statement issued by the Delhi BJP said that "some eminent personalities" will join the party in presence of national vice president Shyam Jaju and state unit president Manoj Tiwari, at its office on Saturday.
Speculation over Mr Mishra joining the BJP was making rounds since he started criticizing the AAP chief after being removed as a minister in May 2017.
He grew close to many Delhi BJP leaders and often shared the stage with them.
His disqualification came into effect from January 27 this year, when he shared the dias with Manoj Tiwari and then Union minister Vijay Goel against the Aam Aadmi Party (AAP), according to the order issued by the speaker.
Two AAP MLAs Devender Sehrawat and Anil Bajpai who joined the BJP during Lok Sabha polls are also facing disqualification proceedings under the anti-defection law.
They had claimed that they had not taken membership of the BJP, although they were impressed with the policies of the prime minister.
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