India has promised to cut its emissions to net zero by 2070 - missing a key goal of the COP26 summit for countries to commit to reach that target by 2050.
Prime Minister Narendra Modi made the pledge, the first time India has set a net zero target, at the Glasgow summit.
Net zero, or becoming carbon neutral, means not adding to the amount of greenhouse gases in the atmosphere.
China has announced plans for carbon neutrality by 2060, while the US and EU aim to hit net zero by 2050.
The Indian leader is one of more than 120 leaders to have gathered in Glasgow for the two-week conference.
Dozens gave speeches on Monday laying out goals to tackle the climate crisis, including UK Prime Minister Boris Johnson, US President Joe Biden and UN Secretary General António Guterres.
President Biden said that every day the world delayed in tackling climate change, the cost of inaction increased.
But he told delegates that the fight against global warming offered incredible opportunities for world economies.
India's net zero pledge
India is the world's fourth biggest emitter of carbon dioxide after China, the US and the EU.
But its huge population means its emissions per capita are much lower than other major world economies. India emitted 1.9 tonnes of CO2 per head of population in 2019, compared with 15.5 tonnes for the US and 12.5 tonnes for Russia that year.
Mr Modi made the pledge as one of five commitments from his country.
They include a promise for India to get 50% of its energy from renewable resources by 2030, and by the same year to reduce total projected carbon emissions by one billion tonnes.
While the 2070 net zero target may have disappointed activists and experts in Glasgow, Mr Modi seems to have impressed people back home.
India had "clearly put the ball in the court of the developed world" by announcing 500 gigawatts (GW) of non-fossil electricity capacity, half of energy from renewables, a reduction of emissions by one billion tonnes and emissions intensity of the GDP by 45% by 2030, according to Arunabha Ghosh, Chief Executive Officer of the Council on Energy, Environment and Water, a leading climate think tank.
"This is real climate action. Now India demands $1tn (£722bn) in climate finance as soon as possible and will monitor not just climate action but also climate finance," Dr Ghosh said.
The BBC's Vikas Pandey reports that the prime minister appears to have found the middle ground for his base - he is seen as being serious about climate change but without compromising India's economic potential.
Most headlines are using words like "big" and "major" to describe the announcement, our correspondent reports.
India's bold step
India's Prime Minister Narendra Modi used most of his time in front of his fellow world leaders to underline the need for lifestyle changes as the greatest solution to climate change.
But Mr Modi saved his biggest news to the last minute.
Detailing what he termed were India's "five elixirs" for climate, Mr Modi announced that his country would adopt a net zero emissions target - by 2070.
This is quite a significant step for the world's third largest emitter, still getting more than 50% of the country's electricity from coal.
It has to be tempered by the fact that the date is far past the mid-century goal for carbon neutrality that scientists say is necessary to avert the most dangerous levels of warming.
But there has been a general welcome for the goal.
'Digging our own graves'
Mr Modi's address came after a strongly worded speech from UN Secretary General António Guterres. Demanding that people stop "treating nature like a toilet" he sharply criticised continued use of fossil fuels, saying "we are digging our own graves".
UK Prime Minister Boris Johnson said future generations "will judge us with bitterness" if they failed at the conference, while US President Joe Biden said that "none of us can escape the worst of what's yet to come if we fail to seize this moment".
But outside the conference on the streets of Scotland's largest city, activists and protesters demanded more from global leaders.
Teenage campaigner Greta Thunberg told a crowd of demonstrators that politicians at the summit are "pretending to take our future seriously".
"Change is not going to come from inside there. That is not leadership. This is leadership. This is what leadership looks like," she said to cheers.