Senior Congress leaders Ramesh Chennithala, V Hanumantha Ra
o, CK Jaffer Shareif and H Hanumanthappa were among the leaders who requested Mukherjee to do a rethink on his decision.
"Congressmen besides secular people are stunned to hear the news and are agitated on the situation and are hopeful that yourself will reconsider the idea.
"I once again request you to reconsider and avoid visiting Sangh Parivar in the interest of secularism and the country," Shareif said in his letter which was also signed by former MP H Hanumanthappa.
"Pranab Mukherjee used to say that the RSS is a bad and the worst organisation in the country. Its leaders have no morals and RSS is corrupt and spreads lies. He (Mukherjee) has also said that the RSS is anti-national, unpatriotic and communal.
"If the RSS has invited a person with such views, does this mean that the RSS admits that his (Pranab's) views about the organisation were correct," Dikshit asked.
However, the Congress patriarch found support from senior party leader Sushil Kumar Shinde, who said Mukherjee accepting the invite was not wrong and "we would be more than pleased" if his thoughts bring some improvement in the RSS.
"Pranab Mukherjee is a secular person. He will always put forth a secular view which he will do there (at the RSS event) as well. He is a very good thinker, and his going there and speaking on that platform is very important," Shinde said.
Former Union Minister P Chidambaram expressed similar views, saying Mukherjee should take the opportunity to tell them what is wrong with their ideology.
"Now that he has accepted the invitation, there is no point in debating why he accepted it.
"The more important thing to say is, Sir you have accepted invitation, please go there and tell them what is wrong with their ideology," said the senior Congress leader.
With agency inputs