WASHINGTON — /twitter.com/TeslaMotors"}}" data-beacon-parsed="true">Tesla founder /twitter.com/elonmusk"}}" data-beacon-parsed="true">Elon Musk, one of nearly 20 business leaders advising President Donald Trump, says he is “cautiously optimistic” about the U.S. staying in the historic /www.huffingtonpost.com/entry/paris-agreement-signed_us_5717f604e4b0479c59d6ec2f"}}" data-beacon-parsed="true">Paris Agreement on climate change.

A Twitter user named Danny Keller asked Musk on Monday if he would “reach out directly with some # ParisClimateAdvice and tell [Trump] to stay in the accord?”

“I spoke directly with The President three weeks ago about Paris,” the billionaire tech entrepreneur responded. “Many others have too. Cautiously optimistic of a positive decision.”

Musk did not elaborate or respond to follow-up questions on Twitter.

@BigDAK54 I spoke directly with The President three weeks ago about Paris. Many others have too. Cautiously optimistic of a positive decision. — Elon Musk (@elonmusk) May 22, 2017

Trump, a longtime climate change skeptic who has dismissed the phenomenon as “bullshit” and a Chinese “hoax,” promised on the campaign trail that he would pull the U.S. out of the Paris climate pact. Members of Trump’s inner circle now find themselves split on how to proceed: Daughter Ivanka Trump and Secretary of State Rex Tillerson are in favor of renegotiating terms, while senior adviser Steve Bannon and EPA Administrator Scott Pruitt are pushing for the president to back out altogether. White House sources told HuffPost earlier this month that Trump is leaning toward an exit.

Last week, Pruitt — who has called the Paris Agreement a “bad business deal” for the U.S. — told Fox News that he expects a decision will be made after the conclusion of a G-7 summit in Italy later this month.

Under the landmark climate accord, nearly 200 countries committed to slashing carbon emissions in an effort to prevent global temperatures from increasing 2 degrees Celsius ― the “magic number” scientists say the world must stay below to prevent the very worst effects of climate change.

Oil giants Royal Dutch Shell and Exxon Mobil Corp., along with hundreds of other businesses, have warned Trump against withdrawing the U.S. from the agreement. Musk and several other CEOs signed an open letter first published in The Wall Street Journal earlier this month, expressing “strong support” for staying in the pact.

Musk has also defended his decision to join the Presidential Advisory Forum. He tweeted in February that “activists should be pushing for more moderates to advise President, not fewer.”

Activists should be pushing for more moderates to advise President, not fewer. How could having only extremists advise him possibly be good? — Elon Musk (@elonmusk) February 5, 2017