US President Donald Trump Thursday referred to what he called the "filthy air" in India, China and Russia as he defended his decision to pull out of the Paris Accord and denounced Democrat rival Joe Biden's plans to tackle climate change in a presidential debate.

"Look at China, how filthy it is. Look at Russia. Look at India. The air is filthy. I walked out of the Paris Accord as we had to take out trillions of dollars and we were treated very unfairly," he said during the second and final debate ahead of the November 3 polls.

"I will not sacrifice millions of jobs... thousands of companies because of the Paris Accord. It is very unfair," he said.

Joe Biden retorted that climate change is "an existential threat to humanity. We have a moral obligation to deal with it."

"We're going to pass the point of no return within the next eight to 10 years," he said.

This is the second time that Trump has made a critical reference to India during a debate. At the first presidential debate, Trump questioned India's coronavirus data. "When you talk about numbers you don't know how many people died in China, you don't know how many people died in Russia, you don't know how many people died in India. They don't exactly give you a straight count," he had said.

The US Presidents remarks drew sharp reactions in India, with some urging Prime Minister Narendra Modi to give a strong rebuttal to Trump's statements. Opposition leaders like Congress's Kapil Sibal seized the comments to take a swipe at PM Modi's well-known bonhomie with President Trump.

https://twitter.com/KapilSibal/status/1319480465535856641

https://twitter.com/AatishTaseer/status/1319464801119178755

https://twitter.com/priyankac19/status/1319476054226948096

Trump charged that Biden's climate plan was an "economic disaster" for oil states such as Texas and Oklahoma.

The planet has already warmed by around one degree Celsius (34 degrees Fahrenheit) from pre-industrial levels, enough to boost the intensity of deadly heat waves, droughts and tropical storms.

Trump has pulled the United States out of the Paris climate accord, which aims to cap global warming "well below" two degrees Celsius.

Trump's remarks come days before Secretary of State Mike Pompeo and Defense Secretary Mark Esper visit New Delhi for talks on building the growing US-India partnership.

At the first presidential debate, Trump also spoke critically of India, questioning its coronavirus data amid criticism of Trump's handling of the pandemic.