BJP will gain in Congress strongholds: Prakash Karat

"We have some experience in the past -- in 1989 and 1996. We can build on that," he added.

In 1989, the CPI-M and other Left parties propped up Prime Minister V.P. Singh's National Front government, which also had the backing of the BJP.

In 1996, the Left played a key role in the formation of the United Front governments of H.D. Deve Gowda and I.K. Gujral which enjoyed the legislative backing of the Congress.

While the CPI took part in the United Front government, the CPI-M refused to lead it when the coalition's members offered prime ministership to veteran Marxist leader Jyoti Basu.

Karat who is currently on a campaign tour of Tamil Nadu was critical of AAP for being "unable to spell out a coherent socio-economic programme".