Scarlett Johansson says she was “shocked” and “angered” at how “eerily similar” one of the voices in ChatGPT sounded to hers.

OpenAI has said it will “pause” the use of one of the voices in ChatGPT after it drew comparisons with the Hollywood actress.

Some users had commented on a similarity between Johansson’s voice and one of the voice options named Sky found inside the app following an update that makes ChatGPT more conversational and even flirtatious, according to some commentators.

Johansson famously provided the voice for the AI interface in the 2013 film Her, set in the near-future and where Joaquin Phoenix’s character slowly falls in love with the virtual assistant.

In a post to X, formerly Twitter, OpenAI said: “We’ve heard questions about how we chose the voices in ChatGPT, especially Sky. We are working to pause the use of Sky while we address them.”

In a statement issued following that post, Johansson said OpenAI chief executive Sam Altman had approached her in September asking her if she would lend her voice to the system, saying he felt it would be “comforting to people” not at ease with the technology.

“He told me that he felt that by my voicing the system, I could bridge the gap between tech companies and creatives and help consumers to feel comfortable with the seismic shift concerning humans and Al,” the actress said.

“After much consideration and for personal reasons, (I) declined the offer.”

The statement continued: “Nine months later, my friends, family and the general public all noted how much the newest system named ‘Sky’ sounded like me.

“When I heard the released demo, I was shocked, angered and in disbelief that Mr Altman would pursue a voice that sounded so eerily similar to mine that my closest friends and news outlets could not tell the difference.”

She said OpenAI “reluctantly” agreed to take down the Sky voice after she hired lawyers who wrote Mr Altman letters asking about the process by which the company came up with the voice.

In a blog post published alongside its X message, the artificial intelligence giant said: “We believe that AI voices should not deliberately mimic a celebrity’s distinctive voice – Sky’s voice is not an imitation of Scarlett Johansson but belongs to a different professional actress using her own natural speaking voice.

“To protect their privacy, we cannot share the names of our voice talents.”

The post added each of the voices ChatGPT uses “has been carefully selected through an extensive process spanning five months involving professional voice actors, talent agencies, casting directors, and industry advisers”.

The company said it had spoken to each shortlisted voice actor about the technology’s capabilities and limitations, as well as its risks and the safeguards the company has in place before deciding on the final five who would be used in the app.

OpenAI unveiled its new AI model, named GPT-4o, last week, with a highlight of the update being the more conversational, human-sounding responses the app’s various voices would now be able to give.

Those updated features have not yet been rolled out, but are due to reach paying Chat-GPT subscribers in the coming weeks.