The theater has appointed external advisers “to help us deal with any information received.”
A spokeswoman for the venue told the UK’s Press Association earlier Tuesday that no complaints had been made against Spacey during his tenure or since his departure.
Spacey said he did not remember the encounter, but was “beyond horrified” by the allegation.
“I owe him the sincerest apology for what would have been deeply inappropriate drunken behavior,” he said in a statement posted to Twitter.
Spacey has not responded to CNN’s request for comment.
Sexual harassment is ‘systemic’
“It’s an opening of the floodgates and it’s a very important moment for all of us,” she said.
“We have a culture across society which has accepted this … it’s deep in our DNA to accept these behaviors. And it’s only now that we’re finding the vocabularies and the confidence and the means to have these conversations,” she added.
Featherstone has been instrumental in drafting a “code of behavior” that will apply to all staff working at the Royal Court Theatre, which will be published later this week.
“It is across every part of our society. If it is not dealt with in an open way we have no hope of change, and change must happen.”
In a statement released by his publicist, Anthony Rapp acknowledged the dialogue begun by the accusations against the powerful movie producer Harvey Weinstein.
“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,” he said.
The actor was due to receive the prestigious award on November 20.
CNN also learned Monday night that US political drama “House of Cards” will conclude after its sixth season, which is currently in production. The decision to end the show was made two months before production began on the season and was not related to the allegation against Spacey, according to two sources.
The company did, however, address the allegation in a joint statement with Media Rights Capital, which produces the series.
“Media Rights Capital and Netflix are deeply troubled by last night’s news concerning Kevin Spacey,” the statement said.
“In response to last night’s revelations, executives from both of our companies arrived in Baltimore this afternoon to meet with our cast and crew to ensure that they continue to feel safe and supported. As previously scheduled, Kevin Spacey is not working on set at this time.”
During his long career, Spacey has won numerous prizes including two Academy Awards, one Golden Globe and several Screen Actors Guild Awards.
He was also presented with an honorary knighthood in the UK by Prince Charles in 2016 for his services to British theater and international culture.
Asked whether Spacey could be stripped of his honor, Siobhan Bruce, interim head of news at the Cabinet Office, told CNN on Tuesday that she could not comment on the allegation.
CNN’s Sandra Gonzalez and Shama Nasinde contributed to this article.