New Delhi: The RSS invite to former President Pranab Mukherjee for an event at its Nagpur headquarters sparked off a controversy, as the Congress and left leaders expressed unhappiness over his acceptance while the BJP and RSS saw nothing wrong in it.

The Rashtriya Swayamsevak Sangh (RSS) said in a statement that Mukherjee's acceptance of the invite for the June 7 function was not "surprising".

Its leader Narender Kumar said that Mukherjee will be the chief guest at the concluding function of "Tritiya Varsh Varg" or third-year course and address the 'swayamsevaks'. RSS chief Mohan Bhagwat will be the main speaker.

"Those who know the sangh and understand it, it is not surprising for them or nothing new. It is normal for them because the RSS has been inviting prominent persons and those engaged in social service. This time, the RSS invited Dr Pranab Mukherjee and it is his greatness to have accepted the invitation," an RSS statement said.

The organisation said that the 25-day "Tritiya Varsh Varg" is held every year at Nagpur in which members from all over the country take part for training.

The statement said that even Mahatma Gandhi visited the RSS camp at Wardha and later stated that he was impressed by the "strict discipline, simplicity and lack of discrimination" in the organisation.

Former President Zakir Husain, socialist leader Jayaprakash Narayan and General (later Field Marshal) K. M. Carriappa were other personalities who attended RSS events.

Union Minister and BJP leader Nitin Gadkari said that there should be an exchange of views and political untouchability was outdated.

"We should meet each other, talk to each other, respect views. The notion of political untouchability is outdated. Those who practice this say others are communal but they are themselves communal," Gadkari said.

Congress Spokesperson Tom Vadakkan did not comment on Mukherjee's acceptance of the RSS invite.

"At this point, I have no comments to offer. Let the event take place first, only after that it will be appropriate to give comments. If you know everything about the history and the specialisation of the RSS and BJP, then I would not like to comment any more on that," he said.

But party leader and former MP Sandeep Dikshit asked if Mukherjee had changed his views on the RSS or the organisation had accepted the views of the former President.

Dikshit said that Mukherjee, who had served the Congress for decades before being appointed President in 2012, had told them that "there is no organisation as cheap, dirty, crafty, untruthful and unpatriotic as the RSS".

He said Mukherjee had said that the RSS should not exist in the country even for a minute.

"Such a person who considers the RSS poisonous, dirty, even worse than snake... such a person is being called by the RSS. On what issue are they calling. Has Pranab Mukherjee changed his views or there is no self-respect left in the RSS," Dikshit said.

Communist Party of India leader D. Raja said that it was for Mukherjee to decide on the invite.

"He is not a child. He is a former President. He was one of the top leaders of the Congress. He has been holding many important positions in the government. He is one of the elderly statesmen in the country today. Whether he has accepted, whether he will go I don't know. It is for him to decide."

"If you ask me, I will say I will not go. Why should I go? I know the RSS agenda. If I were in his place, I will not go," he said.

Rakesh Sinha, who teaches at Delhi University and is Honorary Director of the India Policy Foundation, said Mukherjee's acceptance of the invitation was a message to the nation that on vital issues there should be dialogue and adversaries are not enemies.

"Moreover, the question raised on RSS Hindutva is philosophy of Hinduism by contemporary political forces is being answered by Mukherjee's acceptance of invitation," he said.

Rashtriya Janata Dal leader Manoj Jha said Mukherjee will tell the RSS to "have a delete button in their divisive politics".

"I am sure Pranab Mukherjee ji will tell them what liberal India is," he said.

However, senior party leader Tejashwi Yadav said it was Mukherjee's decision and he would not like to comment.

BJP leader Subramanian Swamy said that the Congress leaders should follow in the footsteps of Mukherjee.

"I think more senior Congressmen should do this because we need a national outlook and that can be done only when outside the political spectrum... they should assemble and educate the people on the virtues of nationalism," he said.

Samajwadi Party Spokesperson Ghanshayam Tewari said too much politics should not be read into the issue.

"It only goes on to prove that once you are President of India, any organisation could seek your guidance," he said.