The ousted leader of ChatGPT-maker OpenAI is returning to the company that fired him late last week, the latest in a saga that has shocked the artificial intelligence industry.

San Francisco-based OpenAI said in a statement late Tuesday: "We have reached an agreement in principle for Sam Altman to return to OpenAI as CEO with a new initial board" made of former Salesforce co-CEO Bret Taylor, former U.S. Treasury Secretary Larry Summers and Quora CEO Adam D'Angelo.

OpenAI's previous board of directors, which included D'ANgelo, had refused to give specific reasons for why it fired Altman on Friday, leading to a weekend of internal conflict at the company and growing outside pressure from the startup's investors.

Microsoft, which has invested billions of dollars in OpenAI and has rights to its technology, quickly moved to hire Altman on Monday, as well as another co-founder and former president, Greg Brockman, who had quit in protest after Altman's removal.

That emboldened a threatened exodus of nearly all of the startup's 770 employees who signed a letter calling for the board's resignation and Altman's return.

Microsoft Chief Technology Officer Kevin Scott put out a call to the startup's employees Tuesday on X, formerly Twitter: "We have seen your petition and appreciate your desire potentially to join Sam Altman at Microsoft's new AI Research Lab. Know that if needed, you have a role at Microsoft that matches your compensation and advances our collective mission."

Microsoft CEO Satya Nadella also made clear in a series of interviews Monday that he was still open to the possibility of Altman returning to OpenAI, so long as the startup's governance and board problems are solved.

Co-founded by Altman as a nonprofit with a mission to safely build so-called artificial general intelligence that's smarter than humans and benefits humanity, OpenAI later became a for-profit business but is still run by its nonprofit board of directors. The board was down to just four members after the departure of Altman and Brockman.

Brockman returned to social media Tuesday as if it were business as usual, touting a feature called ChatGPT Voice that was rolling out for free to everyone who uses the chatbot.

"Give it a try — totally changes the ChatGPT experience," Brockman wrote, flagging a post from OpenAI's main X account that featured a demonstration of the technology playfully winking at recent turmoil.

"It's been a long night for the team and we're hungry. How many 16-inch pizzas should I order for 778 people," the person asks, using the number of people who work at OpenAI. ChatGPT's synthetic voice responded by recommending around 195 pizzas, ensuring everyone gets three slices.