Suman said the the Union Finance Minister telephoned him to inquire about his health and not to seek his vote.
"Will a person of the stature of Pranab Mukherjee ring me up to seek my vote? He never asked me for my vote. But I want him to be the President. He has vision, He is a down to earth person. He is the fittest candidate. I will vote for him," Suman said.
On Trinamool Congress' charge that Mukherjee was trying to break the party by telephoning him, Suman said "he is a gentleman. He is misunderstood."
Asked for comment, Mamata Banerjee, West Bengal chief minister, retorted "we don't comment on such things."
However, other Trinamool Congress leaders reacted sharply to the development and accused Mukherjee of trying to break the party, a charge denied by Congress.
"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 political culture. For Trinamool, politics is a mission. Not a transaction," Derek said.
Senior TMC leader and West Bengal minister Subrata Mukherjee alleged Pranab Mukherjee was trying to break the party.
"A presidential candidate is conspiring to cause a split in the party. If he had to make any call, he should have made it to the party's supreme leader. Telephoning a person who is controversial in the party does not speak well about the purpose. This is unethical," he said.
Though there was no provision of whip in a presidential election, he said, it should be remembered that there were moral obligations.
"It is unfortunate and unethical to make such a phone call to an individual MP or MLA," Urban Development Minister and a close aide of the TC supremo, Firhad Hakim said.
Another Trinamool Congress MP and Union Minister of State for Tourism Sultan Ahmed also expressed unhappiness over the development, saying Mukherjee should not speak to individual leaders of Trinamool, but its chief Mamata Banerjee.
Reacting to this, Congress spokesman Rashid Alvi said "why should we break their party? They are our allies... We have never done it."