"May Justice Krishna Iyer's soul attain eternal peace. My thoughts are with his family during this moment of immense sadness," Modi tweeted.
"Fine lawyer, eminent jurist, incredible philosopher & above all a phenomenal human being. I bow to Justice Krishna Iyer," he said in another tweet.
Recalling his "special" association with Justice Iyer, the Prime Minister said "my mind goes back to our conversations & the insightful letters he would write to me.... Whenever I would meet or talk to him, I would find him full of enthusiasm, always talking about the well-being of India. A remarkable man!"
He had turned 100 on November 13.