France’s new environment minister, Nicolas Hulot, does not mince words when it comes to the possible consequences of Donald Trump pulling the United States out of the Paris climate accord.

Such an act, Hulot said in March, when Trump first signaled that he might withdraw from the agreement to limit carbon emissions, would be “a veritable middle finger to our children,” and could even expose the American president one day to charges of “crimes against humanity.”

Worst of all, Hulot told French television, was the danger that Trump’s action could encourage his fellow climate skeptic, Vladimir Putin, to ignore the restrictions on industrial emissions. Together the two leaders could create, Hulot warned, “an axis of mass destruction between two great powers,” with catastrophic consequences for the planet.

Hulot, who was an environmental activist before joining President Emmanuel Macron’s new government, expressed his concern after Trump ordered the E.P.A. to rescind restrictions on carbon emissions and Putin said that the melting of Arctic ice was most likely a natural process that Russia should take advantage of, not try to stop.

Putin’s remarks, which horrified Hulot, were made during a forum on the future of the Arctic, days after Trump moved ahead with his campaign promise to lift regulations on coal, oil and gas producers imposed by former President Barack Obama.

Speaking in the Russian Arctic city of Arkhangelsk, Putin told the American business channel CNBC that it was “impossible” to stop the warming of the planet, which was more likely caused by “some global cycles on Earth or even of planetary cycles,” than man-made factors like industrial emissions. Climate skeptics, like Trump and E.P.A. head Scott Pruitt, Putin added, “may not be at all silly.”

The only argument Putin offered for this view was an apparently apocryphal story about an Austrian explorer supposedly reporting that Arctic glaciers had already started melting at some point between the 1930s and 1950s. That proved, Putin said, that the melting had started before a spike in industrial emissions.

Even though the explorer Putin cited, Julius von Payer, had visited the Arctic in the 1870s, not the 1930s — and it is not clear if the tale of him describing global warming is fact or fiction — by calling this proof that melting started before man-made emissions, the Russian president appeared to overlook the fact that the industrial revolution was well underway in the 19th century.

Putin has a long history of climate skepticism, which has earned him lavish praise from conspiracy theorists like Alex Jones. His views appear to have changed little since 2003, when he told an international conference that a spike in temperatures would mean Russians could “spend less on fur coats” while “agricultural specialists say our grain production will increase, and thank God for that.”

Although the Russian president surprised some observers at the Paris climate talks two years ago when he pledged to cut Russian emissions of greenhouse gas by 70 percent by 2030, a closer analysis of Russian industrial output showed that the levels Putin proposed would actually represent a 40 percent increase.

As the science writer Hannah Waters explained this week, the Paris accord is less an anti-business measure — as Trump famously claimed when he called it a hoax “created by and for the Chinese in order to make U.S. manufacturing non-competitive” — than “a giant trade agreement to accelerate the development and deployment of renewable energy.”

That is certainly the view taken by the new French president, who said that he tried to convince his American counterpart to stick with the pact during their meeting last week.

That said, Macron, like the leaders of other nations, might not be that sorry to see the U.S. retreat from the development of renewable technologies under Trump. Such a self-inflicted wound could make it easier for French companies to recruit and retain talented researchers, entrepreneurs and engineers who might otherwise join American firms.

To that end, it is worth recalling that in February, even before his election, Macron made a direct appeal to American workers in the field of climate change to move to France, in a video that has racked up more than 23 million views on Facebook and was widely shared on Twitter.