She called on Governor Jagdeep Dhankhar at Raj Bhavan and resigned as the chief minister, as is the practice, before she is administered the oath of office and secrecy again.
She will continue to function in caretaker capacity till then.
Earlier Monday, she addressed a press conference where she spoke of a ''collective fight'' by the opposition against the BJP in the 2024 Lok Sabha elections, but underscored combating the COVID-19 crisis should be the first priority.
''I am just a street fighter. I can boost the morale of the people so that we can fight a strong fight against the BJP. One cannot do everything alone and it should be a collective effort.
''If collectively we can take a decision, together we can fight the battle of 2024. But first let us fight this COVID crisis and then we will decide on this. Now is not the time,'' she said, responding to a question about her role in the 2024 general elections.
Later, the newly elected MLAs of the TMC met and unanimously chose her the leader of the legislature party, before she called on the governor to stake claim to form the government.
Banerjee, who lost from Nandigram despite the astounding TMC victory, can be sworn-in as the chief minister but will have to get elected to the assembly within six months of assuming office.
''CM @MamataOfficial called on me and submitted her resignation as CM and the same has been accepted. She has been requested to continue till alternative arrangements are made,'' Dhankhar tweeted after Banerjee tendered her resignation.
The oath-taking ceremony will be a low-key affair due to an unprecedented surge in COVID-19 cases.
''Taking note of communication @AITCofficial electing @MamataOfficial as leader of 17th WB Legislative Assembly have invited her to take oath of office of Chief Minister on May 5 at 10.45 am at Raj Bhawan. In view of current Covid situation function will be with limited audience,'' he tweeted.
During her media interaction, Banerjee again demanded that every citizen of the country should be given free vaccines by the Centre.
''They are sending vaccine and oxygen to two-three states. Why so? Every state should get its due. I have heard that in Gujarat, vaccine is being given from the BJP party office. Do they (BJP) have any expertise in giving vaccines?'' she claimed.
Banerjee also claimed that the Left, which ruled the state for 34 years on the trot, was unable to get back the votes that it had lost to the BJP in the 2019 Lok Sabha polls, leading to its further downfall.
''I may have political differences with them (Left) but I did not want to see them getting zero. It would have been better if they got the votes back from the BJP. They favoured the BJP so much that they became a signboard. They need to think about this. Dipankar Bhattacharya (CPIM-L) did not do this,'' she said.
The chief minister said she did not get the customary call from Prime Minister Narendra Modi on her victory in the elections.
''This is the first time I saw a prime minister not calling. It is ok, he may be busy. I did not take it in sentiment,'' she said.