Bhowmick said he tendered his resignation to Congress President Sonia Gandhi yesterday alleging that there was no discipline in the party.
"The Congress High Command is a farce and its only duty is to change the TPCC President before the elections to lead the party to a debacle," he alleged.
A former Congress legislator, Bhowmik was defeated in the February 14 assembly elections in which Congress managed only 10 seats in the 60-member House, facilitating CPI-M-led Left Front to retain power for the seventh time with 50 seats.
He said the new party would launch movement against the "misrule" of the Left Front government with Trinamool Congress (TMC).