Oliver Stone fears for the future under Trump: 'We are sleepwalking toward a nuclear nightmare'
Director Oliver Stone poses for photos at the premier for Snowden at the Toronto International Film Festival in Toronto, Ontario, September 9, 2016 (AFP Photo/Geoff Robins)

Oliver Stone has made films on four U.S. presidents and has interviewed Russian President Vladimir Putin for an upcoming documentary -- but he has no idea what story he would tell about Donald Trump.

"This is a little too early to tell if Trump lasts, but it seems he's not to be the kind of president who plans, who deliberates," Stone told The Hollywood Reporter.

The Oscar-winning filmmaker said Trump's presidency has so far "been a disaster," and he worries his presidency poses a possibly existential threat to the world.

"I am very worried about it," Stone said. "I think we are sleepwalking toward a nuclear nightmare. I think when you see my documentary, I think you can understand why."

Stone interviewed Putin four times for a four-hour documentary premiering June 12 on Showtime, and he called for better relations between the U.S. and Russia.

"If you look back in time, World War I, World War II, you will find [the Russians] have been strong allies, and we can return to that position and have a strong alliance with them, which is what we need now,” Stone said.

Stone now regrets cutting a brief Trump cameo from his 2010 film "Money Never Sleeps," a sequel to 1987's "Wall Street," and he compared the president to the subject of his 1995 film, "Nixon."

"If the Trump story may right now be a story about a man who is enamored of consumerism or materialism and wants success at any cost, like Nixon a bit, and comes to the office willing to barter what is left of his soul in order to become president, possibly there is an angle there, but you know, I'm not there yet," Stone said.

"Let's let some years go by and see what happens," he added.