Washington DC - President Donald Trump recently threatened to go after New York Times journalist Maggie Haberman over her reporting about his physical and mental health.

On Saturday, the president shared a Truth Social post in which he described Haberman's newest book, Regime Change: Inside the Imperial Presidency of Donald Trump, as "a joke" and "90%... fake news," and threatened legal consequences.

"She has made a living off her bad reporting, and will pay the price when our Multi Billion Dollar Lawsuit against The Failing New York Times gets to Court," Trump wrote, referring to a $15 billion defamation lawsuit he filed against the outlet last year.

Trump went on to say that if Haberman wrote the true story about him, it would "be quite boring," but "loaded with lots of SUCCESS," such as praise about his health.

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"I just finished a perfect physical at Walter Reed, I do it every six months, and I requested another Cognitive Test, the only President to do so, three times, and I aced them all – Got every question right," Trump proclaimed.

Few people in Washington, DC, could do so, including Maggot and her flunky associate, Jonathan Swan," he added.

Since his return to office, Trump, who just turned 80 years old last month, has been facing heightened concerns about the state of his physical and mental health.

The president has become prone to making bizarre flubs while speaking in public, has fallen asleep multiple times at important events, has made a habit of posting nonsensical things on social media, and has developed visible bruising on various parts of his body.

Despite concerns, Trump has regularly claimed he is in the best health of any president during their time in office in the history of the country.

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His remarks about Haberman came hours after the journalist sat for an interview, during which she claimed Trump's health was "like a black box" within the administration "more than almost any other issue."

"If there is an area of failure in the reporting for us, it was this, and trying to – not mental, per se, but just his health, how he is, why he has gone to Walter Reed [hospital] several times, and they have released less and less information," Haberman argued.

While she declined to comment specifically on Trump's mental acuity, Haberman went on to add, "I think that people can very legitimately question whether 80-year-old people should be president."