San Francisco, May 7 (IANS): The losses of Microsoft-backed OpenAI, the developer behind highly-successful AI chatbot ChatGPT, reportedly swelled to nearly $540 million last year and are likely to only keep rising.

According to The Information, OpenAI's losses doubled as it developed ChatGPT and hired key employees from Google.

"The previously unreported figure reflects the steep costs of training its machine-learning models during the period before it started selling access to the chatbot," the report noted.

OpenAI in February this year launched the new subscription plan, ChatGPT Plus, that is available for $20 a month.

However, the report mentioned that even if the revenue picks up, OpenAI's losses are likely to keep rising as "more customers use its artificial intelligence technology and the company trains future versions of the software".

OpenAI CEO Sam Altman has "privately suggested OpenAI may try to raise as much as $100 billion in the coming years to achieve its aim of developing artificial general intelligence (AGI) that is advanced enough to improve its own capabilities".

Elon Musk, Twitter CEO and an early investor in OpenAI, tweeted late on Saturday: "That's what he (Altman) told me".

Musk, who has criticised OpenAI several times, last month created a new company called X.AI which will promote AI in the ChatGPT era.

It was Musk who initially invested $100 million in OpenAI, but later exited the company.

In recent months, ChatGPT and GPT-4 have become a rage worldwide.

OpenAI recently closed a more than $300 million share sale at a valuation between $27-$29 billion, according to reports.