The president's eldest son will appear before congressional investigators on Wednesday, according to sources cited by Politico. The Associated Press also confirmed the meeting.

The closed interview with the Senate Intelligence Committee marks the third round of questioning for Donald Trump Jr., who met with the Senate Judiciary Committee in September and the House Intelligence Committee last week.

The three committees are conducting independent probes of Russian interference in the 2016 election.

Investigators reportedly asked Trump Jr. at both hearings about a conversation he had with his father, President Donald Trump, regarding the public response to a June 2016 meeting he attended at Trump Tower with Russian lawyer Natalia Veselnitskaya.

That initial statement failed to disclose that Trump Jr. had received promises of incriminating information about Hillary Clinton while setting up the meeting.

The Washington Post reported that the president dictated the public statement about that meeting while aboard Air Force One, according to The Washington Post. Jay Sekulow, the president's attorney, has denied the Post's report, saying the president wasn't involved in drafting the public statement.

Trump Jr. tweet: I met with the Senate Judiciary Committee today. I am thankful for their professionalism and courtesy.

During the summer meeting with the Senate Judiciary Committee, Trump Jr. told investigators that he did not recall the White House's role in crafting the public response, according to CNN.

At last week's meeting with House Intel, Trump Jr. invoked attorney client privilege in denying to answer questions about his conversation with his father about the meeting.

That response drew criticism from experts as well as Democrats on the panel.

"I don't believe you can shield communications between individuals merely by having an attorney present," Rep. Adam Schiff told Politico.

Harry Litman, a former United States attorney and deputy assistant attorney general, told CNBC the justification was "comically over-aggressive."

An attorney for Trump Jr. did not respond to a request for comment.