P Chidambaram remarks comes after PM Modi said country's various languages are an important identity.
Senior Congress leader P Chidambaram, who is lodged in Tihar Jail in connection with the INX Media case, on Sunday said that if the Tamil people are united and speak in one voice, everyone will acknowledge the greatness of their language and culture.
His remarks come days after Prime Minister Narendra Modi, at the Howdy Modi event in the US, had said the country's various languages are an important identity of its liberal and democratic society.
PM Modi had highlighted the importance of linguistic diversity at a time when Home Minister Amit Shah pitched for Hindi as a common language, which drew flak from Opposition parties.
However, Amit Shah had later clarified that he never asked for imposition of Hindi over native languages in the country but advocated its use as the second language.
Mr Chidambaram asked his family to tweet: "If the Tamil people are united and speak in one voice, everyone will acknowledge the greatness of Tamil language and culture."
PM Modi in his UNGA speech on Friday had also invoked famous Tamil philosopher Kaniyan Pungundranar.