Ms Banerjee said the two leaders discussed the current political scenario and strategies to oust the BJP in Assembly and Lok Sabha elections at the 20-minute meeting at Mrs Gandhi's residence.
"I told Soniaji that we want the Congress to be a part of the united opposition," she told reporters later. The Trinamool Congress leader said she stressed that the opposition had to come together to fight the BJP in the states.
"I told her what the country wants is that there should be a state-wise, one-on-one fight with the BJP. The party that is the strongest in the state should contest against the BJP there," she said.
"We want the Congress to win Karnataka because the Congress is strong there," she added.
Ms Banerjee said she also discussed with Mrs Gandhi the talks that she has been holding with the leaders of regional parties. "We are trying to work together...We want the Congress also to be part of that," she said.
The chief minister's meeting with Ms Gandhi was to have been held on Tuesday, but was postponed because the UPA chairperson was indisposed.
The TMC leader had met several opposition leaders on Tuesday, but did not have talks with anyone from the Congress.
"Lalu (Yadav) ji and Sharad (Yadav) ji have an alliance with the Congress. Their alliance will continue," she said, adding that the opposition party which was the strongest in a state should be supported by the others to oust the BJP.
She also lashed out against the BJP while talking to reporters.
"To finish democracy in the country, the BJP is committing atrocities. Apart from political vendetta, the BJP does not do anything," she said.
Ms Banerjee added, "I am 100 per cent sure that when there is one fight, the BJP will go".
The chief minister is in Delhi to hold talks with various parties in a bid to form a united front against the BJP and bring together opposition parties on one platform.
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