Johansson made the comments in a statement released hours after the artificial intelligence company said it was removing the voice, named “Sky.”
OpenAI CEO Sam Altman said in an emailed statement to Reuters on Monday that Sky's voice was not an imitation of Johansson, but of another professional actress.
“Sky's voice is not Scarlett Johansson's, and it was never intended to be similar to hers. We cast the voice actor behind Sky's voice before reaching Ms. Johansson,” Altman said.
“Out of respect for Ms. Johansson, we have discontinued the use of Sky's voice in our products. We apologize, Ms. Johansson, for not communicating better.”
The battle for the rights to actors' voices and images has become a focal point in Hollywood as studios consider how to use AI to create new entertainment and as the computer-generated images and sounds become difficult to distinguish from those of people.
Johansson said in the statement that Altman approached her last September and offered to hire her as a ChatGPT voice — an offer she declined.
“Nine months later, my friends, family and the general public all noticed how much the latest system called 'Sky' looked like me,” she said.
“When I heard the released demo, I was shocked, angry and in disbelief that Mr. Altman would pursue a voice that sounded so uncannily similar to mine that my closest friends and news media couldn't tell the difference.”
Johansson added that Altman had “insinuated that the similarity was intentional” by tweeting a reference to “Her,” the 2013 film about a man who develops a relationship with an AI assistant voiced by the actress.
Johansson's note was published by journalists from NPR and other news outlets. Her publicist also shared it with Reuters.
OpenAI did not immediately respond to a request for comment after Johansson's statement. She said she hired legal counsel to ask about the process of creating the vote.
OpenAI showed off its latest AI model last week, called GPT-4o, with audio capabilities that let users talk to the chatbot and get real-time responses, marking a significant advance in more realistic-sounding AI conversations.