The Oscar winner detailed her uncomfortable experience with an unnamed producer while at the Vulture Festival panel at the Roosevelt Hotel in Los Angeles on Sunday.
"I had a producer invite me to go on a private plane with him with his company somewhere I was going to," Portman said. "And then I was like, 'Yeah, why wouldn't I accept a flight on a private plane with a big group of people?' And I showed up and it was just the two of us and then one bed was made on the plane."
"Nothing happened. I was not assaulted," she continued. "I said, 'This doesn't make me comfortable,' and that was respected but was super not OK."
Portman described the situation as "unacceptable and manipulative," adding that she was "scared."
"There are so many things that we took for granted as part of our world until it changed a month ago," she said of the swarms of sexual misconduct allegations that have recently plagued Hollywood. "A lot of people have been aware of it for a long time, too, but also a lot of things that we just kind of put up with for reasons of maybe just being numb to it from it being so pervasive or people being so upset about it."
Like so many other women and men in Hollywood, Portman expressed her support for all those who have shared their stories of sexual misconduct publicly.
"It's been great that everybody is finally talking about it," she said. "I think my first reaction when I heard everybody coming out was, 'Wow, I'm so lucky that I haven't had this.' And then on reflection, I was like, 'OK, I definitely have never been assaulted. I definitely never. But I've had discrimination or harassment on almost everything I've ever worked on in some way."
"I think every woman has experienced this kind of discrimination," she continued. "People commenting on my body all the time to me, from the time I was a child. Things that are not OK and not on the same level of abuse, but they have a very comfortable enrichment to discrimination where it's not something I ever thought was a reportable offense."