President Trump Donald John TrumpUS reimposes UN sanctions on Iran amid increasing tensions Jeff Flake: Republicans 'should hold the same position' on SCOTUS vacancy as 2016 Trump supporters chant 'Fill that seat' at North Carolina rally MORE on Monday slammed the “people writing books” about him, saying they do not have access and calling their tomes "fake news."

While the president did not specify the subject of his comment, the tweet comes the same day that MSNBC’s Katy Tur released her new book about covering Trump during the 2016 presidential race.

The book, titled "Unbelievable: My Front-Row Seat to the Craziest Campaign in American,” is set to be released Tuesday.

ADVERTISEMENT

In it, Tur describes how Trump singled her out for criticism, sometimes turning the crowds at his campaign rallies against her.

"They turn as one to boo at us in unison. Six thousand Trump supporters railing against 30 or so journalists — caged in the center of the arena like a modern-day Roman Coliseum," Tur writes.

Trump hurled a number of insults at Tur during the campaign, calling her a "third-rate reporter," "disgraceful" and "not nice."

But he didn't mention her directly in Tuesday's tweet.

“Fascinating to watch people writing books and major articles about me and yet they know nothing about me & have zero access. #FAKE NEWS!” Trump wrote.