Prasenjit Bose, a PHD in Economics from JNU and a familiar face in TV channels debate, announced his resignation through an "open letter" arguing that the party Polit Bureau's decision to support Mukherjee was "against" the line taken by the Party Congress held in Kerala earlier this year.
"I protest against the decision by the Polit Bureau to support the candidature of Pranab Mukherjee...I consider this to be a grave error which will harm the party and disturb Left unity," Bose said in the letter.
There was no response from CPI(M) on the resignation of Bose who is the former head of party's research unit.
Bose, who used to appear on news channels to defend the party on Nandigram, Singur land acquisition and other issues, sang a different tune in the letter attacking CPI(M) leadership saying it has committed "one mistake after another since 2007".
He mentioned the "coercive" land acquisition in West Bengal, the Nandigram police firing, allowing the UPA government to approach the IAEA with the Indo-US nuclear deal, giving a call for a non-Congress secular government in 2009 and then accepting them in a "cavalier manner in party conferences without fixing proper responsibility and conducting rectification thereon as the mistakes".
Bose, who is perceived to be close to CPI(M) General Secretary Prakash Karat, had in the recent Party Congress abstained from voting on CPI(M)'s ideological document as they did not agree with it that termed China and North Korea socialist countries.
"The same leadership is committing yet another costly mistake, refusing to learn anything from the past. Party members are aghast and exasperated that their concerns are falling on deaf ears. Therefore, with great pain and agony, I tender my resignation from the primary membership of the Party," Bose said.
He also attacked Karat saying the arguments he put forward where "wholly misleading".
"In the absence of any explicit and coherent explanation so far, one can only make two guesses. If the consideration was that the strength of CPI (M) and the Left is numerically too weak to field its own candidate against both Congress and BJP-backed candidates, then the natural choice should have been to abstain from the polls.
"That is the stand adopted by CPI and the RSP and it is an eminently reasonable, transparent and principled position," he said.