Elon Musk says he's done advising President Trump.
The billionaire founder and CEO of SpaceX said Wednesday (May 31) that he'll resign from the three White House advisory councils on which he sits if Trump pulls the United States out of the Paris climate pact.
Trump announced Thursday (June 1) that he will do just that, prompting an avowal by Musk to follow through on his threat.
"Am departing presidential councils. Climate change is real. Leaving Paris is not good for America or the world," Musk wrote on Twitter today.
The Paris Agreement is an international attempt to slow global warming and mitigate its worst effects. The accord, which involves nearly 200 countries and took years to negotiate, seeks to keep "a global temperature rise this century well below 2 degrees Celsius [3.6 degrees Fahrenheit] above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius [2 degrees F]," according to the United Nations Framework Convention on Climate Change.
Musk has repeatedly voiced concern about climate change and its potential impacts, and the entrepreneur has put his money where his mouth is: In addition to his SpaceX duties, Musk chairs the solar-energy company SolarCity and is the CEO of electric-car maker Tesla. (You can get the latest climate news from Live Science, Space.com's sister site.)
Trump, on the other hand, has long expressed skepticism about the need for action on climate change. For example, in November 2012, he said on Twitter that "the concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive."
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The president later walked back that particular tweet, saying it was a joke. But he has referred to climate change and-or global warming as a hoax on several other occasions as well.
Musk currently serves on Trump's manufacturing jobs council and infrastructure council, as well as the president's strategic and policy forum, according to CNBC.
Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.