New Delhi, Feb 16: Tamil is the oldest and a beautiful language, Prime Minister Narendra Modi said on Friday, regretting that he was not able to speak it. "Tamil is the oldest language. It is older than Sanskrit and is beautiful. I can only say 'vanakkam' (greeting) and I regret I cannot go beyond this," he said in a chat here with school students. Modi was answering questions at an interaction with the students in a special programme "pariksha pe charcha" (discussion on examinations). Modi, who spoke in Hindi during the entire interaction, also apologized to students that he could not speak to them in other languages. He hoped translated versions of his interaction would be available in other languages.