"I have taken the decision. Only the procedures have to be followed," Karunakaran told television channels ahead of his faction's crucial convention to he held in Thrissur on May 1.
"I think it is proper on my part to resign when it becomes difficult to continue in the post," the octogenarian leader who has, of late, been on a collision course with the party high command, said.
Evading a direct reply whether he will put in his papers before the May 1 convention, Karunakaran said: "I have made up my mind to resign and the question whether it is to be done at the convention or after is just a matter of procedure."
Karunakaran, the seniormost Congress leader and three-time chief minister of Kerala, was elected to the Rajya Sabha in April 2004.
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