A new interim chief executive has been appointed to the company behind major AI chatbot ChatGPT, with the ousted ex-CEO Sam Altman being tapped up to head a new Microsoft AI team.

Mr Altman, the founder of OpenAI and former CEO, was fired in a shock announcement on Friday, as the not-for-profit company board said Mr Altman "was not consistently candid in his communications with the board".

The detail behind the alleged lack of candour was not published and the true reason for the sacking remains unclear.

There had been speculation that Mr Altman could return to the company after he posted a photo of himself wearing an OpenAI guest pass on social media platform X but Microsoft's chief executive on Monday announced Mr Altman would join Microsoft to lead a new advanced AI research team.

Microsoft has invested billions of dollars into OpenAI as it developed its generative AI model, ChatGPT, which gave millions of people the ability to have questions answered by artificial intelligence (AI).

Microsoft was reported to only have been given a minute notice of Mr Altman's exit.

Earlier, the New York Times, based on an OpenAI memo, said OpenAI's board stood by Mr Altman's firing.

It reported that Emmett Shear, who was chief executive at Amazon's streaming platform Twitch, has been appointed as the new interim CEO.

Microsoft CEO Satya Nadella also confirmed Mr Shear's reported appointment, saying the company was "looking forward to getting to know Emmett Shear and OAI's new leadership team and working with them".

In a statement that confirmed Mr Altman's appointment, Mr Nadella added that OpenAI's former president Greg Brockman would also be joining.

The departure of Mr Altman on Friday led to the resignation of OpenAI president, Greg Brockman, in support.

Mr Shear replaces Mira Murati - the firm's chief technology officer, who was put in place as OpenAI's interim chief executive on Friday.

According to online technology website The Information, dozens of staff quit at OpenAI after its chief scientist Ilya Sutskever announced Mr Altman would not be returning.

The Information report said Mr Sutskever told OpenAI staff Mr Altman's behaviour and board interactions had undermined the company's ability to supervise artificial intelligence development.

Mr Altman said of his departure: "Today was a weird experience in many ways.

"But one unexpected one is that it has been sorta like reading your own eulogy while you're still alive. The outpouring of love is awesome."