India on Wednesday rejected calls to announce a net zero carbon emissions target and said it was more important for the world to lay out a pathway to reduce such emissions and avert a dangerous rise in global temperatures.

India, the world's third-biggest emitter of greenhouse gases after China and the United States, is under pressure to announce plans to become carbon neutral by mid-century or thereabouts at next week's climate conference in Glasgow.

But environment secretary R.P.Gupta told reporters that announcing net zero was not the solution to the climate crisis.

"It is how much carbon you are going to put in the atmosphere before reaching net zero that is more important."

The United States, Britain and the European Union have set a target date of 2050 to reach net zero, by which point they will only emit an amount of greenhouse gases that can be absorbed by forests, crops, soils and still-embryonic "carbon capture technology.

China and Saudi Arabia have both set targets of 2060, but these are largely meaningless without tangible action now, critics say.

Between now and the middle of the century the United States will release 92 gigatons of carbon into the atmosphere and the EU 62 gigatons, Gupta said, citing Indian government calculations. China would have added a staggering 450 gigatons by its net zero target date, he added.

Representatives of nearly 200 countries will meet in Glasgow, Scotland, from October 31-November 12 for climate talks to strengthen action to tackle global warming under the 2015 Paris Agreement.

Indian Prime Minister Narendra Modi will attend the conference in a sign of how the country is taking climate change seriously, officials say. Chinese President Xi Jinping is not expected.

While working towards net zero, countries are expected to announce new and strengthened intermediate targets for cutting emissions.

Environment Minister Bhupendra Yadav said India was on track to achieve targets set at the 2015 Paris conference and left the door open to revising them. "All options are on the table," he said.

India has committed to cutting the emissions intensity of its GDP by 33-35 percent by 2030 from 2005 levels, achieving a 24 percent reduction by 2016.

Some environment experts say India could consider lowering its emissions intensity by as much as 40 percent dependent on finance and whether it has access to newer technologies.

Yadav said he would measure the success of the Glasgow conference by how much it delivered on climate finance to help the developing world cut their emissions while ensuring economic growth.