The announcement was made at Microsoft’s Build developer conference on Monday, and was notable given Microsoft’s partnership with OpenAI. Musk founded xAI, the startup behind Grok, but he has also been locked in a feud with OpenAI since stepping down from its board in the late 2010s, citing disagreements over its leadership direction.

Microsoft Corp. (MSFT), which leapfrogged to the pole position in artificial intelligence technology (AI), riding on strategic partner OpenAI’s advanced large-language models (LLM), has begun to look elsewhere.