After tendering his resignation from the INC, former Assam Congress president and Rajya Sabha MP Ripun Bora joined the All India Trinamool Congress (TMC) on Sunday, 17 April.
In his resignation letter addressed to party president Sonia Gandhi, Bora said that instead of putting up a united front against the BJP, the Congress leadership engaged in constant infighting for vested interests.
He also suggested that senior party leaders maintained a "secret understanding" with Assam Chief Minister Himanta Biswa Sarma.
"I am very pained to inform you that it is an open secret in Assam that instead of fighting against the BJP, a section of senior most leaders of Assam PCC have been maintaining a secret understanding with the BJP government, mainly with the Chief Minister."Ripun Bora, in his resignation letter