Donald Trump Jr. told Fox News' Sean Hannity Tuesday he will commit to testifying under oath about a June 2016 meeting with a Russian lawyer, a meeting he claims he never mentioned to his father.

The Fox interview was the first since Trump Jr. released emails Tuesday confirming not only his involvement in arranging a meeting with the lawyer regarding potentially damaging information about Hillary Clinton, but also that he was told such information was part of the Russian government's support of then-candidate Donald Trump. The eldest Trump son insisted he told his father nothing of the meeting.

"No," Trump Jr. responded when Hannity asked if he'd told his father about the June 9 meeting with the Russian attorney, Natalia Veselnitskaya. "It was such a nothing. There was nothing to tell."

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President Trump tweeted Wednesday morning about his son's appearance with Hannity:

My son Donald did a good job last night. He was open, transparent and innocent. This is the greatest Witch Hunt in political history. Sad! — Donald J. Trump (@realDonaldTrump) July 12, 2017

Trump Jr. said this was the first and last time he met with Veselnitskaya, and insisted this meeting was the furthest extent of any ties to Russia. Trump Jr. confirmed some details from Veselnitskaya's account of their meeting, saying he likely pressed her for more on information that would damage Clinton. But the eldest Trump son also said he "probably" met with others from Russia.

"I've probably met with other people from Russia ...not in the context of actual, a formalized meeting or anything like that, because why would I?" Trump Jr. said.

Trump Jr. blamed his decision to move forward with the meeting in the way he did on his newness to the political scene, saying he's "still way in the learning curve on all of this."

"In retrospect, I probably would have done things a little differently," Trump Jr. also said. "Again, this is before the Russia mania. This is before they were building it up in the press. For me, this was opposition research... So, I think I wanted to hear it out. But really, it went nowhere and it was apparent that that wasn't what the meeting was actually about."

The eldest Trump son released the emails between himself and Russia-connected publicist Rob Goldstone after The New York Times reported that they existed.

Here's my statement and the full email chain pic.twitter.com/x050r5n5LQ — Donald Trump Jr. (@DonaldJTrumpJr) July 11, 2017

Here is page 4 (which did not post due to space constraints). pic.twitter.com/z1Xi4nr2gq — Donald Trump Jr. (@DonaldJTrumpJr) July 11, 2017

"This is obviously very high level and sensitive information but is part of Russia and its government's support for Mr. Trump -- helped along by Aras and Emin," Goldstone wrote on June 3, 2016, at 10:36 a.m. The email continues, "I can also send this info to your father via Rhona, but it is ultra sensitive so wanted to send to you first."

Shortly after that, at 10:53 a.m., the eldest Trump son responded, "Thanks Rob I appreciate that. I am on the road at the moment but perhaps I just speak to Emin first. Seems we have some time and if it's what you say I love it especially later in the summer. Could we do a call first thing next week when I am back?"

The emails contradict previous denials of contact between the Trump campaign and Russia.

The White House has declined to comment on the emails, other than a brief statement from President Trump that White House deputy press secretary Sarah Huckabee Sanders read Tuesday afternoon: "My son is a high-quality person and I applaud his transparency."

The president also tweeted his support for his son shortly before the Hannity interview was set to air, saying Trump Jr. "is a great person who loves our country!"

My son, Donald, will be interviewed by @seanhannity tonight at 10:00 P.M. He is a great person who loves our country! — Donald J. Trump (@realDonaldTrump) July 12, 2017

The Senate Intelligence Committee wants to interview Trump Jr., and email exchanges -- as well as his meeting with the lawyer -- fall under the mandate of special counsel Robert Mueller's FBI investigation into any collusion between the Trump campaign and Russian government. Trump Jr. said he would provide any relevant documents.

Democrats have described the email chain as a game changer, and Republicans were troubled, too, Nancy Cordes reported.

Vice President Mike Pence appeared to distance himself from the Trump Jr. email story Tuesday.

"The vice president is working every day to advance the president's agenda, which is what the American people sent us here to do," said Marc Lotter, a spokesman for the vice president. "The vice president was not aware of the meeting. He is not focused on stories about the campaign, particularly stories about the time before he joined the ticket."