Agartala,  The Trinamool Congress as part of its efforts to expand organisational base in the northeastern states including the BJP-ruled Assam and Tripura, would celebrate the party's foundation day on January 1 by organising mega events, party leaders said on Monday.

Trinamool sources said that party supremo and West Bengal Chief Minister Mamata Banerjee, and National General Secretary Abhishek Banerjee would visit Assam and Meghalaya this month to strengthen party organisations in the two northeastern states.

Meghalaya opposition leader Mukul Sangma, along with 11 Congress MLAs joined the Trinamool Congress (TMC) last month claiming that the Congress has failed as an effective opposition in the country, and the TMC would be a pan-India viable alternative opposition party. The latest political development in the northeast state is a major boost for Banerjee, who after the March-April assembly election success in her state, has been trying to expand her party's footprint beyond Bengal.

Meghalaya is the newest state as Bengal's ruling party in its expansion mission, mainly at the expense of the Congress. It has also made inroads in Tripura, Goa, Assam, Uttar Pradesh, Bihar and Haryana.

TMC's Rajya Sabha member Sushmita Dev on Monday said that the ruling Bharatiya Janata Party (BJP) in Tripura is frightened after going through the Trinamool Congress' vote share in the recent civic polls.

"People have seen how BJP restored its vote share through rigging, booth jamming, attacking and intimidating the opposition parties and also adopting other unfair means," Dev told the media.

She said that party leaders would visit every Tripura village to make the people aware about the misgovernance of the BJP and their anti-people policies.

"To highlight the common people's issues, a 'Raj Bhawan Abhiyan' (march to Raj Bhawan) would be organised next month. There are some fake news in the media that the party is isolating its cadre. We are in constant touch with those who have been attacked in the state," the parliamentarian said.

Tripura Trinamool Convener Subal Bhowmik said that it is the democratic right of every political party to hold campaigns.

"But the BJP government, most of the times, has not allowed the Trinamool Congress to hold any organisational event in the state. During the recently held civic polls, the state authorities denied permission for several Trinamool campaigns," Bhowmik said.