San Francisco, California - Twitch co-founder Emmett Shear confirmed his appointment as OpenAI's new CEO on Monday, days after the AI firm fired Sam Altman.

"Today I got a call inviting me to consider a once-in-a-lifetime opportunity: to become the interim CEO of @OpenAI. After consulting with my family and reflecting on it for just a few hours, I accepted," he said in a post on X, formerly Twitter.

OpenAI's board sacked its former CEO Altman on Friday, prompting other high-profile departures from the company as well as a reported push by major investors to bring the co-founder back.

In his post, Shear denied that Altman had been fired over safety concerns.

"Before I took the job, I checked on the reasoning behind the change. The board did *not* remove Sam over any specific disagreement on safety, their reasoning was completely different from that," he wrote.

"I'm not crazy enough to take this job without board support for commercializing our awesome models."

An hour before Shear's post, Microsoft CEO Satya Nadella confirmed he was hiring Altman to lead an AI research team at the global tech titan.

"We look forward to getting to know Emmett Shear and OAI's new leadership team and working with them," Nadella added in a post on X.