Jeff Bezos regained his spot as the world's fourth-richest person.
Jeff Bezo delivers remarks at the grand opening of the new Washington Post newsroom in Washington, Jan. 28, 2016. Reuters/Gary Cameron

The founder of at least one company in the race to send humans to Mars is still willing to put at least one high-profile passenger on board a rocket to take him out of Earth’s atmosphere for good.

Blue Origin founder and Amazon CEO Jeff Bezos joked Thursday about a past offer to save a seat for Republican presidential nominee Donald Trump on one of the rockets they’re planning on sending to the red planet. “I have a rocket company, so the capability is there,” Bezos said at Vanity Fair’s New Establishment Summit, according to Gizmodo.

Bezos tweeted last year that he would reserve Trump a seat on a Blue Origin rocket after his fellow billionaire called Amazon a “no profit company.” These days, Bezos is a little more cautious: At the event, he indicated that he regretted being flip about the idea last December and said that he sees Trump as a very real threat to the United States.

Of Trump’s comments this week that he may not accept the results of the election in November, Bezos said he sees a threat to American democracy. “That erodes our democracy around the edges,” he said.

Bezos and Trump have had some beef for a while now. Bezos, one of the richest men in the world, also owns the Washington Post, a paper that Trump has repeatedly criticized and tried to silence by denying reporters there access to his events.

Trump’s attempt “to try to chill the media and sort of threaten retribution, retaliation, which is what he’s done in a number of cases, it just isn’t appropriate,” Bezos said Thursday.

Blue Origins is competing with Elon Musk’s SpaceX, Boeing and NASA in the race to land humans on Mars. That competition could yield results relatively soon: President Barack Obama has said that NASA will land an astronaut on the planet by 2030.