Carl Bernstein is expressing no comfort with President Trump's decision to switch up his chief of staff. Alluding to an attempt to fix a "problem," Bernstein said the real issue is Trump himself.

"The problem is not the chief of staff. The problem — dangerous beyond any modern presidency — is the president," he tweeted early Saturday.

On Friday, Trump announced that Homeland Security Secretary John Kelly would take Reince Priebus' job as chief of staff. The move came after months of speculation that Priebus would be ousted and days of accusations of leaking flung in his direction by new communications director Anthony Scaramucci.

Bernstein, best known for his investigative reporting that shed light on the Watergate scandal leading to President Richard Nixon's resignation in 1974, has previously said Trump's attacks on the press are more dangerous than Nixon's. He also said Trump's firing of FBI Director James Comey in May was a "dangerous" situation.