The head of America's Environmental Protection Agency (EPA) has reportedly been deluged with angry phone calls after publicly doubting the role that carbon dioxide plays in climate change.

The Washington Post said that "according to three agency employees", calls to Scott Pruitt's main office number were so relentless on Friday that "agency officials created an impromptu call centre".

One employee apparently told the paper that interns were asked to answer some of the calls.

The EPA did not speak to the Post directly.

Meanwhile, a blog on the Union of Concerned Scientists' website said: "Dear Scott Pruitt: Stop lying. We see what you are doing."


Is climate change a priority for Trump?

Mr Pruitt sparked the controversy when he contradicted his own organisation's advice by saying he does not believe that carbon dioxide is a main contributor to global warming.

Speaking on CNBC show Squawk Box, he said: "I think that measuring with precision human activity on the climate is something very challenging to do and there's tremendous disagreement about the degree of impact, so no, I would not agree that it's a primary contributor to the global warming that we see."

He added: "We need to continue the debate and continue the review and the analysis."

His own organisation's position on the subject is summarised on its website, which says: "Carbon dioxide is the primary greenhouse gas that is contributing to recent climate change."

Mr Pruitt's position also differs from that of the National Oceanic and Atmospheric Administration (NOAA), and NASA.

Image: Mr Pruitt addressing Environmental Protection Agency employees

NASA and the NOAA said in January that surface temperatures of the Earth during 2016 were "the warmest since modern recordkeeping began in 1880".

The organisations added: "The planet's average surface temperature has risen about 2 degrees Fahrenheit (1.1 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere."

Mr Pruitt, who was sworn in last month, has previously served as Oklahoma's attorney general.

When his appointment was announced in December, a news release from Donald Trump's transition team quoted Mr Trump as saying: "For too long, the Environmental Protection Agency has spent taxpayer dollars on an out-of-control anti-energy agenda that has destroyed millions of jobs, while also undermining our incredible farmers and many other businesses and industries at every turn."