Chidambaram said now that the former president has accepted the invitation he should go and tell the RSS "what is wrong" in their ideology.
"Now that he accepted the invitation it is wrong to discuss whether he should have accepted or not. I wouldn't have accepted. But now that he accepted, he should go there and tell them what is wrong with their ideology," Chidambaram said.
His party colleague and senior lawyer Abhishek Singhvi opined that the party would like to first hear what Mukherjee has to say before making any comments.
"It is wrong to judge someone from accepting of an invitation. Unless we listen to someone we should not make opinion. I have also written for Panchjanya and Organiser, it was very well accepted within my party," Shingvi said.
Pranab, who has been a Congress veteran, has been invited to be the chief guest at the valedictory function of Sangh Shiksha Varg -- a training camp for RSS volunteers at the organisation's headquarters in Nagpur on June 7. According to an RSS functionary, the former president has accepted the invitation.
On Tuesday, Former MP and Delhi Congress leader Sandeep Dikshit had said as a Congress leader and minister, Mukherjee has spoken about the RSS and the BJP many times on various issues and dubbed it as "bad" and "worst" outfit, which is "communal" and "anti-national".
"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 had asked.
Former union minister C K Jaffer Sharief had also urged Pranab to reconsider his decision. Sharief said that it was surprising that Mukherjee has taken a decision like that.
"We are very good old friends...this sudden visit to Nagpur is something surprising, which we never expected," Sharief told PTI.
Mukherjee was above politics now, Sharief said, adding, he (Mukherjee) cannot forget his past. "If he (Mukherjee) has reached this level, it is because of the Congress," he said.