While on Watch What Happens Live With Andy Cohen earlier this week, the Vox Lux actress was asked who is the better kisser. Portman had a response at the ready immediately.
"Mila! I mean, obviously," Portman said.
Portman acted opposite Kunis in Darren Aronofksy's Black Swan, which earned her an Oscar in 2011. That same year, she starred in Ivan Reitman's romantic comedy No Strings Attached, in which she and Kutcher played friends who try to have a physical relationship before learning they love each other.
Kunis and Kuthcer both starred in That '70s Show and married in 2015. Since That '70s Show ended in 2006, Kunis and Kutcher have only acted together once - in a movie-within-a-movie in the 2014 Annie remake, so do not expect to see them kissing each other on the big screen.
"Probably not going to happen," Kunis told Sunday Today when asked if she would ever make a movie with Kutcher again. "I can't look at him and not be like, 'What are you doing?'…No, it's weird."
Kunis said the two would get too distracted by watching each other acting.
"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 Willie Geist in August. "You can catch each other on like the weird shtick so to speak."
Meanwhile, Portman is happily married to dancer and choreographer Benjamin Millepied, who choreographed the ballet scenes in Black Swan. They married in 2012 and have two children, Aleph and Amalia.
While on WWHL, Portman said it was "pretty close" to love at first sight.
"He parked backwards on the street - like, I saw him... we were on a first floor studio - and he parked [in] the wrong direction and I was like, OK... that fits!"
The actress also defended Ahmed Best, the actor who played Jar Jar Binks in Star Wars: Episode I - The Phantom Menace.
"Ahmed Best, who played Jar Jar, is one of my very good friends and he is so talented and so wonderful and I was very angry that they said bad things about him," Portman told Cohen.
Portman can now be seen in Brady Corbet's Vox Lux, in which she plays a pop star. Earlier this year, she appeared in Alex Garland's Annihilation and she hosted Saturday Night Live in February.
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