Cara Delevingne decided against reporting being sexually harassed because she "didn't want to publicly ruin someone's life".

Cara Delevingne

Cara Delevingne

The 26-year-old actress has joined the thousands of women on Twitter who have been sharing their stories of abuse and harassment under the hashtag WhyIDidntReport.

Cara wrote: "Because I felt ashamed of what happened and didn't want to publicly ruin someone's life, even though they privately ruined mine #WhyIDidntReport (sic)"

When Cara first told her story, she refused to reveal the identity of her alleged harasser.

But in October last year, the British star admitted that the allegations were against the movie producer Harvey Weinstein.

Cara discussed the alleged incident in an Instagram post, accusing Weinstein of making advances towards her in a hotel room after asking the actress to kiss another woman.

In a lengthy message on the photo-sharing website, she said: "As soon as we were alone he began to brag about all the actresses he had slept with and how he had made their careers and spoke about other inappropriate things of a sexual nature.

"He then invited me to his room. I quickly declined and asked his assistant if my car was outside. She said it wasn't and wouldn't be for a bit and I should go to his room. At that moment I felt very powerless and scared but didn't want to act that way hoping that I was wrong about the situation.

"When I arrived I was relieved to find another woman in his room and thought immediately I was safe. He asked us to kiss and she began some sort of advances upon his direction. I swiftly got up and asked him if he knew that I could sing. And I began to sing....i thought it would make the situation better....more an audition....i was so nervous.

"After singing I said again that I had to leave. He walked me to the door and stood in front of it and tried to kiss me on the lips. I stopped him and managed to get out of the room. (sic)"