"I am not stopping my struggles I have undertaken so far. I will continue my fights against corruption, communalism and to protect the nature, soil and pride of Kerala until my last breath," the 92-year-old veteran said in a facebook post.
Achuthanandan, who was described as 'warhorse' and 'Kerala's Fidel Castro' by CPI(M) general secretary, Sitaram Yechury, had spearheaded the LDF's election campaign and helped it secure a massive victory over Congress-led UDF in the May 16 assembly polls.
"But people, who always stood with me in my fights, have given me all support. They have ushered in LDF by giving them a historic mandate of 91 seats," he said.
Referring to the fierce state-wide campaign he undertook, the former chief minister said he had to fulfill a "historic responsibility" at the May 16 polls and that was why he had decided to contest accepting the direction of the party central leadership.
While announcing that he was stepping down as Opposition leader, Achuthanandan had said here yesterday that he would continue to play the role of a "sentinel" of the people of Kerala.
He was elected from Malampuzha constituency in Palakkad by a margin of 27,142 votes.