"Probably not going to happen," Kunis said in an interview with Willie Geist for Sunday Today. "I can't look at him and not be like, 'What are you doing?'…No, it's weird."
In other words, the two would get distracted by each other while trying to act.
"In a scene with him I was like 'Oh I see you acting.' Like I can catch it...and he looked at me and was like 'What's that face you make?' And I was like 'We can't do this. We can't be together in a scene,'" Kunis told Geist. "You can catch each other on like the weird shtick so to speak."
Kunis and Kutcher have only acted together once since That '70s Show ended in 2006. They both had cameos in the 2014 Annie remake, appearing in the MoonQuake Lake movie-within-a-movie.
Although Kunis has no plans on working with Kutcher in a movie again, she is interested in making a third Bad Moms movie with Kristen Bell and Kathryn Hahn. But it would have to be "done right without being rushed," Kunis told Geist.
The first Bad Moms was a surprise box office hit in 2016, making $186 million worldwide. The sequel, A Bad Moms Christmas, was less successful, but still made $130.5 million on a $28 million budget.
There has also been talk of a That '70s Show reboot, which would definitely require Kunis and Kutcher to act together again. In April, Kunis told Entertainment Tonight she was open to the idea, even if her real-life marriage might make things weird on the set.
"You know, maybe? I can't say 'no,' because we're all still very good friends, but we're all in such different places in our life," Kunis told ET. "We're not as interesting as Roseanne. Nobody wants to see us back together... [And] it'd be like [in the] 1990's."
More recently, co-star Topher Grace told The Hollywood Reporter he would be interested in a '70s Show revival.
"I would do it for sure because that was a very wonderful time for us. We were all very close, having that experience every single day with each other," Grace said in May. "It was great to broadcast it out once a week, but, like, I'm still great friends with those guys."
Kunis can now be seen on the big screen in The Spy Who Dumped Me with Kate McKinnon and Kutcher stars on Netflix's The Ranch.
Photo credit: Alberto E. Rodriguez/Getty Images for Disney