The Trinamool Congress's Tripura unit former chief Surajit Datta on Friday joined the Bharatiya Janata Party (BJP) in the presence of Assam Chief Minister Sarbananda Sonowal and other senior leaders."I have joined the BJP to strengthen the struggle to dislodge the Left Front government in next year's assembly elections," Datta, who resigned from the party last week, told reporters after formally joining the BJP.He said: "I have resigned from the TMC as the party would be unable to fight against the ruling Left Front properly."A former minister and former President of the Tripura Pradesh Congress Committee, Datta joined the TMC in September 2013 along with many leaders and thousands of followers.Datta, a five-time Congress member of the state assembly, joined the BJP at a massive public rally addressed by Assam Chief Minister Sarbananda Sonowal, BJP's National General Secretary Ram Madhav and state unit president Biplab Kumar Deb among other leaders.Refusing to comment on Datta's resignation, Tripura state TMC's President Ashish Saha said the TMC would fight tooth and nail against the ruling Left Front government in next year's assembly elections.Veteran tribal leader Rampada Jamatia also joined the BJP at the public gathering.