Speaking at a public meeting in Hyderabad at the conclusion of the party's 22nd Congress, he said the third front should have a strong basis and policy under which it should be formed and would emerge only through public movements.
He said the Telangana Chief Minister spoke with him some days ago, wanting to bring a Non-Congress and non-BJP front.
"He asked my opinion. I said the third front exercise was done about 20 years ago in 1996. We formed a government under the leadership of Deve Gowda without the BJP and Congress."
Mr Yechury said the question now is what is the main expectation of the third front and on what policies would it be formed.
"The front that will be formed specifically to come into power will not work. We will take a decision based on the policies on which the front would be formed," he said.
According to news agency PTI, Mr Yechury said, "defeating religious-based politics and 'religious fanatics' was the prime objective."
"We will decide what sort of strategy is to be followed during elections. They will not be defeated through mere poll alliances. We will have to strengthen public movements to defeat them," he said.
Mr Yechury alleged that the Modi government waived Rupees 3 lakh crore worth of loans to 'big capitalists' like Nirav Modi.
According to news agency PTI, Mr Yechury also alleged that "Many of the persons involved in atrocities against children and women belong to RSS and BJP and that the government had failed to act against such people."
"There are no cases against them. On the contrary cases are filed against the victims. We have never faced such a state of affairs before this regime," he alleged.
"They dictate what we should eat and who should be our friends," he said.
Describing PM Modi as "Duryodhana" and Amit Shah as "Dushyasana" of the epic Mahabharat, he claimed that the CPI(M) would defeat 'communal forces' through public movements.
Mr Yechury went on to allege that the PM Modi-led NDA Government had failed on all fronts, including providing Minimum Support Price to farmers.
Kerala Chief Minister Pinarayi Vijayan said development of the country was hampered due to the 'neo-liberal' policies of the present government.
He claimed that permanent jobs in all sectors had vanished due to the 'hire and fire' policies followed by employers.
Mr Vijayan then highlighted some of the developmental measures being undertaken by his government in Kerala.
Speaking at the event, former Tripura Chief Minister Manik Sarkar said, "only the Left party can provide an alternative to the Congress and the BJP.
"BJP cannot be the alternative of the Congress, and Congress cannot be the alternative to the BJP. They are two sides of the same coin. Only the Left and democratic forces can provide that alternative. That situation will emerge through movements only," he said.
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