The United States will meet its climate agreement goals, UN special envoy for climate change Michael Bloomberg said in Paris on Thursday.

"They have given us a roadmap of what we must do to save this planet. And I can only tell you that in America we will meet our COP21 goals," the former New York mayor said.

The United States is one of 60 countries committed to the COP21 climate deal struck in Paris in December 2015, though recent comments by President Donald Trump have raised concern among environmentalists.

Bloomberg's comments came as the incoming head of the US Environmental Protection Agency said that carbon dioxide is not the main driver of global warming, a position starkly at odds with the scientific consensus on climate change.

Trump's team is reportedly divided over whether the United States should withdraw from the Paris climate accord, negotiated under his predecessor Barack Obama.

Bloomberg, in the French capital for talks with President Francois Hollande and Paris Mayor Anne Hidalgo, said he hoped Trump would "be a leader" on the issue.

"My hope is that the new president of the United States, once he gets into office for a period of time, will come to understand that he can also be a leader as President Hollande is in terms of helping us prepare for our future," he told AFP.

He added the US was "basically" 60 percent of the way to achieving its COP21 climate goals.

"It's being done by the private sector helping close coal power plants, corporations looking at their environmental footprint and trying to improve it... and the average citizen in America understanding that climate change is real," he told AFP.

Hildago said city mayors in France, the United States and elsewhere "know that the measures to reduce carbon emissions also contribute towards clear air, boost the economy and improve the quality of life."