Delhi Chief Minister Arvind Kejriwal has written to Prime Minister Narendra Modi urging him to bestow Bharat Ratna on noted environmentalist Sunderlal Bahuguna as the country celebrates its 75th anniversary year of independence.

The letter written by Kejriwal on Saturday said, "We believe presenting Bharat Ratna to Sunderlal Bahuguna will yield honour for the award itself."

Bahuguna, known for his lifelong work to conserve nature in the hill state of Uttarakhand, started "Chipko Andolan" to save trees from being cut that spread to other states as well. He passed away at the age of 94 on May 21 this year.

Kejriwal had raised the demand for Bharat Ratna on Friday at a programme organised at Delhi Vidhan Sabha to pay homage to the world-renowned environmentalist.

"In this 75th year of independence of the country as we are honouring freedom fighters and those eminent personalities who gave a right direction to the nation, I request you on the behalf of Delhi government to felicitate Sunderlal Bahuguna with Bharat Ratna," it read.

Bahuguna dedicated himself to the cause of environment conservation by sensing the imminent threat to the world, at a time when it was exploiting the nature with closed eyes and environment conservation was absent in global discourse, Kejriwal said.

He had cautioned that humans have committed error to treat nature as private property and unchecked exploitation was going to cause various anomalies and problems, said the Chief Minister.

"I hope that you will consider this request by Delhi government and take a proper decision in this regard as soon as possible," Kejriwal wrote to Modi.

It is the good fortune of the people of India that a personality like Sunderlal Bahuguna was born here as his entire life is inspiring for all of us, the CM said.

The ruling Aam Aadmi Party in Delhi has demanded Bharat Ratna for Bahuguna, who hailed from Uttarakhand which is going to Assembly polls next year. The party has been actively engaged in preparations for the elections.

Kejriwal said a portrait of Bahuguna has been installed in Delhi Assembly so that his life and work of environment protection inspires and guides policymakers of Delhi.