Woodward, an investigative journalist and the author of an upcoming book about the Trump administration called "Fear," insists that, though Defense Secretary James Mattis and White House Chief of Staff John Kelly have publicly denied quotes attributed to them in the book, his quotes are actually correct.
When asked by a "Today" show host Monday whether Kelly and Mattis were lying, Woodward replied: "They are not telling the truth."
"These are political statements to protect their jobs, totally understandable," he added.
Both officials denied quotes attributed to them.
On the show, Woodward admitted that sources "frequently" deny in public information that is shared 0 sometimes by them — in private.
"Have you ever done one of these books, know you talked to a source, and the source comes out publicly after the publication and says, 'That's not true?'" the host asked.
"It happens frequently," Woodward replied.
Over Twitter, the US president attacked Woodward and his book, calling Woodward a "liar," accusing him of making up quotes (some from 45 himself), and pointing out that the book is to be published right before the midterm congressional elections.