The Trinamool and the congress had formed an alliance in the 2009 Lok Sabha and 2011 West Bengal assembly polls, but they broke off last September when the Trinamool walked out over the central government's decisions to hike diesel prices and allow FDI in retail.
The Trinamool leadership has announced it would slap show cause notices on Lok Sabha members Kunal Ghosh, Tapas Pal and Satabdi Roy for their anti-party comments at a programme last Friday.
Trinamool MP Somen Mitra, who has been sidelined in the party, is said to be the rallying point for the dissidents.
