More than a dozen lawmakers have discussed President Trump with a Yale University psychiatrist who edited a book rejecting her field's longstanding principle that it is unethical for psychiatrists to issue a diagnosis without a personal exam.

Dr. Brandy Lee, who has not examined Trump, spoke to more than a dozen Democratic lawmakers and one Republican senator, she told Politico in a report published Wednesday. Lee declined to identify the Republican.

She predicted to lawmakers that Trump was “going to unravel, and we are seeing the signs.” The meetings took place on Dec. 5 and 6.

Lee is editor of The Dangerous Case of Donald Trump, which includes testimonials from 27 psychiatrists and mental health experts. The book rejects the longstanding "Goldwater rule," the ethical stance of the American Psychiatric Association that psychiatrists should never offer diagnostic opinions about people they haven't personally examined.

Dr. Jeffrey Lieberman, former president for the American Psychiatric Association, has said that the book is “not a serious, scholarly, civic-minded work, but simply tawdry, indulgent, fatuous tabloid psychiatry.”

Trump's tweets and speeches have brought about various denunciations from his critics. Before Trump's election, former President Barack Obama called him "unfit to serve." Rep. Zoe Lofgren, D-Calif., introduced a resolution in August calling for a mental and physical exam of the president to remove him from office.

Questions were raised anew this week after Trump tweeted about North Korea.

“Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger & more powerful one than his, and my Button works!” Trump tweeted Tuesday.

In response to questions about the president's mental health, press secretary Sarah Sanders said the country should instead be worried about North Korean leader Kim Jong Un.

“The president and the people of this country should be concerned about the mental fitness of the leader of North Korea,” she said during the daily briefing. “This is a president who is not going to cower down.”

Trump will undergo a routine physical at Walter Reed National Military Medical Center in Bethesda, Md., on Jan. 12, the White House said. As with past presidents, it is unlikely to include an in-depth psychiatric analysis.