P.C. George was disqualified as a Kerala assembly member by Speaker N. Sakthan on Friday.
The development came a day after the estranged Kerala Congress (Mani) legislator submitted his resignation.
The Kerala Congress (Mani) is a member of the ruling Congress-led United Democratic Front.
George submitted his resignation on Thursday, the speaker told reporters here.
"He (George) was disqualified because his party had submitted a petition that he has violated the rules and his disqualification comes after going through all the procedures," said Sakthan.
Sakthan said he stands disqualified from June 3.
George, 65, a six-time legislator, is currently suspended from his party for his constant attack on party chief and former finance minister K.M. Mani.
George, who hails from Poonjar in Kottayam district, began his political career through the student movement in the early 1970s.
He became a legislator for the first time in 1980. Since 1996, George has never lost from Poonjar constituency.
George said: "I will seek legal advice... because the rules say that as and when a handwritten resignation letter is submitted directly by the legislator, it should be accepted and it becomes valid from the time it is given."
