India ratified the Paris climate agreement on Sunday, becoming the 62nd country to join the historic accord that could go into force by the end of the year.
The deal, agreed to in the French capital in December, is the first universal action plan aimed at keeping global temperature increases within two degrees of pre-industrial levels.
India, the world's fourth largest carbon emitter, played a crucial role in negotiations during the Paris climate summit, where it used its influence to speak out on behalf on developing countries.
But New Delhi said it had delayed ratifying the treaty in order to consider its implications on India's economic advancement
China and the US ratified the agreement last month. The European Union is expected to do so this week.
The deal formally takes effect 30 days after two conditions have been met: firstly, that it has been ratified by at least 55 countries; and secondly, that those countries account for at least 55 per cent of global greenhouse gas emissions.
A statement from the UN Secretary General's office said that with India on board, the treaty now covers 52 per cent of emissions.
"India's leadership moves the world an important step closer toward the 55 per cent threshold needed for the historic agreement's entry into force this year," the statement said.
India filed the documents ratifying the treaty with the United Nations in New York, the country's Environment Minister Anil Madhav Dave said.
India will push strongly for the protection of the rights of developing nations at the Marrakesh Climate Change Conference in November, he said.
Dave said that at Morocco, where the next session of the UN-sponsored climate change talks are to be held, India would raise the issues of finance and technology transfer to developing nations to help them combat climate change.
India had decided to ratify the Paris agreement on October 2, which is Mahatma Gandhi's birthday, because it is imperative that people across the world chang their lifestyles to one that is more Gandhian, he said.
Gandhi, the leader of India's freedom movement, advocated a simple lifestyle which used all resources in an economical manner.
"No amount of seminars or negotiations would lead to success unless we adopt this lifestyle," Dave said.