The alleged encounter happened 1986.
Kevin Spacey has been accused of making a sexual advance on a 14-year-old actor in 1986.
Spacey responded to the accusations by Star Trek: Discovery star Anthony Rapp in a statement in which he also came out as gay after years of famously keeping quiet about his personal life.
"I'm beyond horrified to hear his story," the House of Cards actor, 58, wrote in a tweet posted at midnight Monday. "I honestly do not recall the encounter, it would have been over 30 years ago."
Rapp, now 46, has been a working actor since he was 9 years old, performing in numerous shows in the 80s and 90s that included the original stage production of Rent. At the same time, Spacey was making a name for himself on Broadway.
Rapp told BuzzFeed that Spacey invited him to his apartment for a party one night, where he carried Rapp to a bed and laid on top of him.
"He was trying to seduce me," Rapp recalled. "I don't know if I would have used that language. But I was aware that he was trying to get with me sexually."
In his statement, Spacey did not admit to Rapp's accusations but apologized nonetheless for any potentially "drunken behavior."
"If I did behave then as he describes I owe him the sincerest apology for what would have been deeply inappropriate drunken behavior, and I am sorry for the feelings he describes having carried with him all these years," Spacey wrote.
In a move that has confounded some, Spacey used the statement as an opportunity to come out of the closet.
"This story has encouraged me to address other things about my life. I know that there are other stories out there about me and that some have been fueled by the fact that I have been so protective of my privacy," he wrote. "I now choose to live as a gay man."
Spacey's decision to come out at this conspicuous moment has drawn criticism from the likes of sex columnist Dan Savage, comedian Billy Eichner and Rose McGowan, who has played a highly visible role in defending victims of sexual abuse in recent weeks.
"Nope to Kevin Spacey's statement. Nope. There's no amount of drunk or closeted that excuses or explains away assaulting a 14-year-old child," Savage tweeted early Monday.
Eichner joked: "Kevin Spacey has just invented something that has never existed before: a bad time to come out... That Kevin Spacey statement. Nope. Absolutely not. Nope."
McGowan tweeted: "Gay = Gay Predator = Predator" as well as "Bye bye, Spacey goodbye, it’s your turn to cry, that’s why we’ve gotta say goodbye."
After Sunday's BuzzFeed story started to make national headlines, Rapp took to Twitter, as well, but to say he's done discussing the accusations for now.
"I came forward with my story, standing on the shoulders of the many courageous women and men who have been speaking out to shine a light and hopefully make a difference, as they have done for me. Everything I wanted to say about my experience is in that article, and I have no further comment about it at this time," he wrote.