Former Assam Congress President Ripun Bora on Sunday joined the Trinamool Congress.

“From today, I have started my new political journey,” the former Rajya Sabha MP wrote on Twitter.

In his resignation to Congress, Bora alleged that some leaders from the party’s Assam unit have a “secret understanding” with the Bharatiya Janata Party and Chief Minister Himanta Biswa Sarma.

This is not the first time Bora has accused some Congress leaders of favouring the BJP. On March 30, a day before elections to two Rajya Sabha Assam seats, he had alleged that the Congress did not know that some of its MLAs were going to join the BJP.

Bora was contesting for one of the seats. However, before the elections, Congress had accused the All India United Democratic Front of favouring BJP’s candidate. The Badruddin Ajmal-led party too had claimed that some Congress workers would be voting against Bora.

During the elections, Congress MLA Siddique Ahmed’s vote was cancelled as he wrote “one” instead of numeric 1. In a statement, the Assam Pradesh Congress Committee said that Siddique had intentionally violated the direction of the chief whip of the party.

BJP’s Pabitra Margherita won unopposed by securing 46 votes.

On Sunday, Bora in his resignation letter said that the party’s interest and ideology are being compromised.

“The leaders of this grand only congress party at fighting each other for their vested interests,” he said. “This has given BJP ample advantages to grow in every nook and corner in one hand and another, demoralising millions of congress workers of the country.”

He also expressed gratitude to Congress President Sonia Gandhi in the letter.

“I have been associated with the INC [Indian National Congress] since 1976, right from my student life and during this long period I served the party at different capacity with party and constitutional posts,” he wrote. “But today, with a heavy heart, I tender my resignation.”