Mary Bowerman

USA TODAY Network

Stephen Hawking fears he "may not be welcome" in the United States while Donald Trump is president.

The science superstar told Piers Morgan during an interview on ITV's Good Morning Britain on Monday, that the liberal hysteria over Trump's presidency may have been "overdone," but said his election marks a definite "right wing" and "more authoritarian approach" in the U.S.

Hawking, who has said multiple times that human-caused climate change is one of the greatest threats to humankind, was also fiercely critical of Trump's appointment of Scott Pruitt to the Environmental Protection Agency.

Pruitt, who has sued the EPA as Oklahoma's attorney general to block clean air and water regulations from being enforced, recently told CNBC that he doesn't agree that carbon dioxide emissions from human activity are the "primary contributor" to climate change.

Hawking told Morgan that Pruitt's stance on climate change is exactly why Trump should rethink Pruitt's appointment.

"He should replace Scott Pruitt at the Environmental Protection Agency," Hawking said. "Climate change is one of the great dangers we face and its one we can prevent. It affects America badly, so tackling it should win votes for his second term — God forbid."

While Hawking believes he may not be welcome in the United States, he is welcome somewhere few will ever have the chance to go. Hawking said Richard Branson offered him the chance to go to space.

He told Morgan the beyond his family the thing that will make him most happy is "to travel in space."

"I have already completed a zero gravity flight which allowed me to float weightless, but my ultimate ambition is to fly into space," Hawking said. "I thought no one would take me, but Richard Branson has offered me a seat on Virgin Galactic and I said yes immediately. Since that day I have never changed my mind."

Oh yeah, and as for whether he's the smartest person on the planet?

"I would never claim this, people who boast about their IQ are losers," Hawking said.

Watch the full interview here:

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