"Pranab M directly called up a TMC MP seeking support. Politically ethical to do? Or trying to break TMC? Try & try again. Won't break," Trinamool Congress MP Derek O'Brien said on micro blogging site Twitter.
"Spare us from petty parleys and incestuous intrigues of Delhi's [ Images ] political culture. For Trinamool politics is a mission. Not a transaction," Derek said.
Mukherjee had called up dissident Trinamool Congress MP Kabir Suman who said that he would vote for him.
Suman said the the Union Finance Minister telephoned him to inquire about his health and not to seek his vote.
Reacting to O'Brien's charge, Congress spokesman Rashid Alvi said, "Why should we break their party? They are our allies... We have never done it."