In a big setback for the Trinamool Congress (TMC), senior leader and MP Mukul Roy has resigned from the party's working committee.

Once a trusted lieutenant of TMC supremo and West Bengal Chief Minister Mamata Banerjee, Mukul Roy today announced that he will resign from the party's primary membership and the Rajya Sabha MP's post after Durga Puja. "I will reveal why I am resigning from the party after Durga Puja," said Mukul Roy, adding that he was "forced" to leave the party.

Hours after Mukul Roy's announcement, the Trinamool Congress leader Partha Chatterjee said that Roy has been expelled from the party for six years.