Trinamool Congress leader Krishna Chakraborty on Thursday resigned as the mayor of the Bidhannagar Municipal Corporation, citing personal reasons and expressing a desire to focus on her role as a councillor after serving in the post for 16 years.

A long-time associate of Trinamool Congress supremo and former West Bengal chief minister Mamata Banerjee, Chakraborty submitted her resignation to the municipal commissioner earlier in the day, officials said.

"This is entirely my personal decision. I have been in this chair for 16 years. I have no grudge against anyone. I have followed the rules to resign. I want to give some time to myself. I want to work as a councillor," Chakraborty told reporters.

Officials of the civic body confirmed receiving her resignation letter.

"We have received her letter expressing her desire to step down. She has also marked copies of her resignation to the municipal affairs minister and the additional chief secretary of the department," an official said.