They were reacting to Union Home Minister Amit Shah's tweet on the importance of India having one language to have a global identity.
"India is a country of different languages, and every language has its own importance. But it's important to have a language of the whole country, which should become the identity of India in the world. Today, if one language can do the work of unifying the country, then it's Hindi, the most spoken language," Shah said in a series of tweets on the occasion of Hindi Diwas.
Responding to a media query on Shah's tweet, DMK chief M.K. Stalin said, "It's shocking. It will surely affect India's unity. On behalf of the DMK, I would urge him to take back that view of his."
The party would decide how to mark its opposition to such views, Stalin added.
PMK Founder S. Ramadoss tweeted, "Shah's views on Hindi to be India's single language is wrong. He has the right to speak high of Hindi language on the Hindi Day. But Hindi can't be forced on the people speaking other languages."
Ramadoss said, just because Hindi was spoken by a large number of people in India, it could not be a unifying force. "If Hindi is imposed on people speaking other languages then it will break the country. There are global examples for this," he said.
Interestingly, Tamil is an official language in Sri Lanka and Singapore.
( With inputs from IANS )