Elon Musk had sharp words for a private-sector partnership touted this week by the Trump administration to hasten the development of artificial intelligence infrastructure. “They don’t actually have the money,” Musk said of two of the participants in the $500 billion initiative, OpenAI and SoftBank, on his social media site X.

The location suggests that Mr. Musk, who owns companies with billions of dollars in contracts with the federal government, will continue to have remarkable access to President-elect Donald J. Trump.