Bhattacharya told a news conference that he had personally delivered a letter dated November 16 to Chief Minister Mamata Banerjee requesting that he be relieved of his responsibility in view of his "unsound physical and mental condition" and the bypass surgery he had undergone last year.
"The chief minister on receiving the letter said I cannot be spared. But I stick to my decision," he said.
Asked by reporters if was quitting as an MLA too, he said, "If it can be interpreted that way, so it is."
He, however, said he was not going to join any other political party and would remain a loyal Trinamool supporter.
Asked if he had attended the administrative meeting at the Singur BDO office, where Mamata was present, today, he said he had not received any formal invitation letter in this regard.
Bhattacharya, a retired teacher, had expressed unhappiness at being shunted to the Statistics and Programme Implementation Ministry from Agriculture in a recent ministerial reshuffle, arguing the shift indicated the party's lack of faith in his ability to perform.
He had also alleged that TMC party men were taking "cut money" in exchange for services rendered and referred to allegations of exchange of money in school appointments in Singur.
Bhattacharya had played a key role in the agitation against Tata Motor's small car factory in Singur which ultimately saw the relocation of the factory to Sanand in Gujarat, but handed the Trinamool Congress rich rewards in the Assembly elections which it won.
