Veteran journalist Carl Bernstein is concerned that President Trump is attempting to "sabotage" special counsel Robert Mueller's investigation into Russian interference in the 2016 election and called on Republicans who might be trying to shield the commander in chief to "put principle above party."

Instead of encouraging compliance with Mueller's probe, Bernstein, during an interview with CNN on Friday, said Trump "has sought to muddy the waters" by vilifying his 2016 campaign opponent Hillary Clinton.

"It's very conspicuous," Bernstein told CNN's Don Lemon.

He said Mueller "ought to be able to have the opportunity, without the president of the United States trying to sabotage his investigations, to follow through." Just before the interview, it was reported by CNN that the first charges had been filed his Mueller's investigation.

Bernstein, best known for his investigative reporting that shed light on the Watergate scandal leading to President Richard Nixon's resignation in 1974, tied the current situation to the Watergate era.

"If there is no there there, we have every right to expect that Robert Mueller would say so," Bernstein said. "But we also — I do go back to Watergate and think of a time when Republicans were those who said we will put principle above party. We want to see these investigations of Richard Nixon proceed. Let the facts come fall where they may. That's really what we need now."