Birx, whose book on the Trump administration and the pandemic is released Tuesday, told ABC News’ Jennifer Ashton that she “immediately went to his most senior staff” and told them his comments must “be reversed immediately.”

“And by the next morning, the president was saying that was a joke,” Birx said. “But I think he knew by that evening, clearly, that this was dangerous.”

Worth noting: Birx said on ABC’s “Good Morning America” that she regretted not saying more at the time Trump made the comments.

“I just wanted it to be ‘The Twilight Zone’ and all go away,” Birx said of the moment Trump made the disinfectant comments in front of the cameras as she sat in her seat at the news conference.