Kabir, the MLA from Rejinagar in Murshidabad district said in a letter faxed to WBPCC President Pradip Bhattacherjee and Chowdhury, that he was quitting the party and all posts.
"I resigned from all Congress posts. I will also put in my papers as MLA and join the Trinamool Congress on November 20," he said from Rejinagar.
"I have already got in touch with Chief Minister Mamata Banerjee and held talks with TMC's all India General Secretary Mukul Roy," he said.
Kabir is likely to be inducted in the ministry in a reshuffle expected next week.
To a question, Kabir said he would meet Assembly Speaker Biman Banerjee on November 20 to submit his resignation as MLA and discuss the technicalities of his quitting the Congress.
Kabir, a first time MLA and an associate of Adhir Chowdhury since 1998 was not getting along well with him. He was also the Murshidabad district Congress and president of the party's district kisan cell.
He also claimed that he quit the party as it had lost confidence in building up a proper movement against the CPI(M).
Another Congress MLA Krishnendu Chowdhury from the Congress stronghold of Malda district would join the Trinamool Congress on November 20 and is likely to be inducted into the ministry in the ministerial reshuffle.
"I will join Trinamool Congress on November 20 in Kolkata," Krishnendu Chowdhury, chairman of the Englishbazar Municipality in Malda district told PTI over phone.
He, however, evaded a query whether he would resign as MLA.
Murshidabad district party secretary Mafuz Alam said it was unfortunate that Kabir resigned to join TMC 'to fulfil his personal ambitions'.
WBPCC chief Pradip Bhattacherjee had said that it was clear that the sole agenda of the TMC appeared to breakup of the Congress in the state.
