Trump sons dismiss Russia investigation 'witch hunt,' but will watch Comey testimony Eric and Donald Trump Jr. agree with their father’s labeling of Russia probe.

 -- As the country readies for fired FBI Director James Comey’s blockbuster testimony on Capitol Hill on Thursday, President Trump’s two adult sons say that despite their doubts about the ongoing investigations into possible collusion between Trump’s campaign and Russia, they also plan to tune in.

In an exclusive interview with ABC News’ Chief National Correspondent Tom Llamas, Eric and Donald Trump Jr. agreed with their father’s labeling of the Russia probe as “a witch hunt.”

“It's the greatest hoax of all time,” Eric Trump said Monday in Trump Tower. “I was there throughout the campaign. We have no dealings in Russia. We have no projects in Russia. We have nothing to do with Russia.”

Despite mounting political pressure from both sides of the aisle, both argued the investigations are merely a byproduct of fake stories and leaks from “holdovers” looking to tank the Trump’s administration.

“I definitely see a political establishment working to make it difficult for him to succeed,” Donald Trump Jr. said. “But I don't know enough about the details of Comey and what he's gonna do there.”

Both sons said they have not been contacted by anyone at the FBI asking for an interview or information regarding the Russia investigation. Eric Trump dismissed the idea that the recent appointment of Robert Mueller as a special counsel should be read as bringing any new legitimacy to the investigation.

“I mean, I really think they had to, optically,” he said. “But it is nothing more than a witch hunt. At the end of the day, I really believe nothing will come out of this in any way.”

ABC News reported recently that both Eric and Donald Trump Jr. were visited by the FBI on May 8 -- the day before Comey’s firing -- regarding an attempted overseas cyberattack against the Trump Organization.

Both brothers said there was no discussion of the Russia investigation in that meeting, and no contact with their father was made following the meeting regarding the attempted hack or Comey specifically.

“Obviously, as a company in America, we're susceptible like so many others to potential cyberattacks,” Donald Trump Jr. said. “And so that was the extent of what I can actually talk about. But it had nothing to do with the [Russia investigation].”