"On World Environment Day, we reaffirm our commitment to a cleaner and sustainable planet. Living in harmony with nature is a part of the Indian ethos. India is committed to addressing climate change and bequeathing a greener, eco-friendly habitat to our children," Kovind tweeted.
Naidu also pledged to protect the nature and environment. In a tweet, he urged the people to reduce dependence on fossil fuels and to adopt renewable resources.
"On World Environment Day, let us take a firm pledge to protect nature and environment by saving energy, water, reducing use of disposable plastics, promoting reusable materials, planting saplings and reducing dependence on fossil fuels by adopting renewables," he said.
Modi also took to Twitter and said, "Our planet and environment is something we all cherish greatly. Today, on World Environment Day, we reiterate our commitment to ensure a cleaner planet. Living in harmony with nature will lead to a better future."
He also shared a video of his visits to places with natural beauty.
Union Home Minister Amit Shah, Himachal Pradesh Chief Minister Jai Ram Thakur and Punjab Chief Minister Amarinder Singh were among other leaders who urged the people to follow eco-friendly behaviour.
Union Environment Minister Prakash Javadekar, External Affairs Minister S. Jaishankar and other leaders planted trees and urged fellow citizens to do the same.
The day is celebrated annually since 1974 across the globe to encourage awareness and action for protection of environment. This year, the United Nations Environment Programme has chosen air pollution as the theme.
( With inputs from IANS )