Former Union Minister and ex-BJP MP Babul Supriyo formally joined the Trinamool Congress (TMC) on Saturday. Supriyo had quit the Bharatiya Janata Party (BJP) following the recent Union Cabinet reshuffle."I will continue to work constitutionally as an MP in Asansol. Politics is beyond the constitutional post and I withdraw myself from it. I will not join any other party. I will vacate the MP bungalow in Delhi and release security personnel from their duties soon," he was quoted saying.