Besides Chidambaram, other Congress leaders including Anand Sharma and Randeep Surjewala also lauded Mukherjee's speech at the event.
Speaking ahead of Mukherjee's speech, Bhagwat said Mukherjee will remain what he is and the Sangh will remain the Sangh even after the event.
Mukherjee's decision to attent the RSS event has already triggered a major political slugfest with several Congress leaders criticising his decision.
Congress senior spokesperson Anand Sharma took to Twitter to express his anguish soon after images of Mukherjee attending a function at the RSS headquarters in Nagpur appeared on television.
Mukherjee, who had arrived in the city on Wednesday night, went to the RSS founder Dr K BHedgewar's residence near RSS headquarters in the Mahal area of the city around noon.
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