West Bengal Chief Minister Mamata Banerjee sat overnight in front of Dalit icon Dr B R Ambedkar's statue on Red Road in the heart of the metropolis, surrounded by a cohort of TMC leaders and workers under television camera arclights.

Banerjee, who is staging a two-day sit-in to protest alleged discrimination by the Centre against the state, had Wednesday in a change of stance urged all political parties in the country to unitedly fight the BJP in next year's Lok Sabha election.

This is a departure from an earlier decision to remain equidistant from both the Congress and the right-wing party ruling India's federal polity.

The Trinamool Congress supremo was accompanied by several party leaders, including Firhad Hakim and Aroop Biswas at the protest site.

Banerjee's 30-hour demonstration is likely to end around 7 pm on Thursday.

Security measures in and around the venue were tightened keeping in mind the presence of high-profile leaders, a senior officer of Kolkata Police said.

Banerjee started the sit-in from Wednesday noon, protesting against the Centre's "stoppage" of funds to the state for MGNREGA and other schemes of the housing and public works departments.

Stating that the 2024 Parliamentary polls will be a fight between the citizens of the country and the BJP, Banerjee had Wednesday asserted that people across religions must unite to defeat the saffron party and save the poor of the country.

She described the BJP as 'Dushasana' and 'Duryodhana' – the two antagonists from the epic ‘Mahabharata'.

"I urge every political party in India to unite to oust this ‘Dushasana' BJP government. ‘This Duryodhana' BJP should be removed from power to save the country's common man as well as Indian democracy," Banerjee said.

Kolkata has been witnessing a flurry of political activity ahead of the panchayat elections slated for this summer, which has now received a green signal from the Calcutta High Court.

The state's political temperature has risen by a few notches with rallies by Banerjee's nephew and TMC leader Abhisek, BJP's Suvendu Adhikari and a march organised by the Left-Congress alliance, alongside the sit-in, which has been drawing large crowds of onlookers.