Nineteen Trinamool Congress MPs have sent a signed letter to the Lok Sabha Speaker's office, with sources telling NDTV the list includes senior party figures such as Kakoli Ghosh Dastidar, Satabdi Roy, Saayoni Ghosh, Yusuf Pathan, and June Malia.
The development is a significant escalation in the rebellion against party chief Mamata Banerjee following the Trinamool's crushing defeat in the Bengal Assembly election.
A 20th Trinamool leader, described by sources as a "big name," is expected to sign soon, NDTV reported.
The signed letter to the Speaker's office signals that the rebellion has moved beyond internal complaints into formal parliamentary action, raising questions about the Trinamool's future as an opposition bloc in the Lok Sabha.
Among the rebels' major complaints are allegations Mamata Banerjee has lost touch with ground realities, in the state and in the party, and allowed corruption to take root in both, NDTV reported, citing the letter.
The rebels have also complained about the Trinamool chief's nephew - Abhishek Banerjee, the party's National General Secretary and second-in-command - being given too much power, the letter added.
The rebellion has been building since the May election, in which the Trinamool won just 80 seats against the BJP's 208, losing power in West Bengal for the first time in 15 years.
Since then, discontent over Mamata Banerjee's leadership has grown steadily, with rebels alleging she has lost touch with ground realities and allowed corruption to take root in the party and the state.
A parallel grievance centres on the outsized role of her nephew Abhishek Banerjee, the party's National General Secretary, whom rebels accuse of concentrating power at the expense of senior leaders.
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Satabdi Roy, a four-time MP who has been with Mamata Banerjee since 2009, told NDTV the former chief minister had changed, and that the change had pushed her toward supporting the BJP.
"I am leaving because our voices were unheard. I want to work for the people... but no one heard us. Only selective people had access to Mamata Banerjee," she said, also citing corruption within the party.
The crisis deepened Thursday when veteran leader Kalyan Banerjee — one of Mamata's strongest supporters — publicly turned on Abhishek Banerjee.
"His arrogant attitude has destroyed the party," he fumed, adding that Abhishek "thinks he is the king." Banerjee issued a blunt ultimatum to Mamata: "She has to decide... if she cannot move the party forward without Abhishek, then I will not be there."
The outburst followed reports that Abhishek had removed Kalyan as his lawyer in a forgery case without informing him directly, NDTV reported.
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