James Biden tells House committee that Joe 'has never had any involvement' in his business dealings

James Biden, the president's younger brother, told lawmakers at a closed-door deposition before the House Oversight Committee on Wednesday that the president "has never had any involvement or any direct or indirect financial interest" in his family's business ventures -- a key point Republicans are disputing in their ongoing impeachment inquiry into President Joe Biden.

James Biden appeared before the GOP-controlled panel that said it has gathered scores of bank records and witness testimony as part of its effort to further an unproven theory that President Biden improperly supported and benefitted from his family's overseas business affairs.

James Biden, 74, is a witness at the center of those allegations. During his deposition Wednesday, lawmakers are questioning him for the first time.

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During his opening statement, James Biden said he kept business separate from his personal relationship with Joe Biden.

"Because of my intimate knowledge of my brother's personal integrity and character, as well as my own strong ethics, I have always kept my professional life separate from our close personal relationship," James Biden said. "I never asked my brother to take any official action on behalf of me, my business associates, or anyone else."

Republicans have accused the president's son, Hunter Biden, and, to a lesser extent, James Biden, of serving as conduits for Joe Biden to quietly benefit from their foreign business arrangements -- allegations the White House has forcefully denied.

"In every business venture in which I have been involved, I have relied on my own talent, judgment, skill, and personal relationships - and never my status as Joe Biden's brother," James Biden said during his opening statements. "Those who have said or thought otherwise were either mistaken, ill informed, or flat-out lying."

The top Democrat on the House Oversight Committee, Rep. Jamie Raskin, told reporters that he has not heard anything from James Biden indicating that President Joe Biden had "anything to do with the business ventures of Hunter Biden or James Biden."

Raskin wouldn't answer questions from reporters on the specifics of the ongoing interview with James Biden

"I will allow the Republicans to reconstruct for you whatever they're trying to accomplish, but I can assure you that he has restated our basic understanding ... which is that Joe Biden had nothing to do with these business ventures," Raskin added. "He was not involved in any way and he was not receiving any money from them. He was not a business partner, or a business associate."

Prior to James Biden's visit to Capitol Hill Wednesday, several key witnesses interviewed as part of the impeachment probe have shared exculpatory accounts that undercut key tenets of Republicans' accusations against the president.

Republicans are nonetheless expected to press James Biden on his role in allegedly selling the Biden "brand" and proclivity to invoke his family name in business negotiations, as ABC News has previously reported.

On Wednesday morning, Rep. Jim Jordan, R-Ohio, said the focus of Wednesday's interview with James Biden will be "the money, the business, the brand."

Oversight Committee Chairman James Comer, R-Ky., has separately taken a keen interest in two checks collectively worth $240,000 that James Biden sent his brother, Joe Biden, in 2017 and 2018.

Comer has framed those transactions -- which occurred after Biden left the vice presidency and before launching his presidential bid -- as evidence that he received "laundered" money from James Biden's business deals, including one with a Chinese energy firm.

But bank records obtained separately by ABC News indicate they were repayments for loans that Joe Biden had made to his brother around the same time. Images of the physical checks support that conclusion, with each of them characterized in the memo line as a "loan repayment."

James Biden addressed the two personal checks on Wednesday, saying in his opening statement that they were "short-term loans that I received from Joe when he was a private citizen, and I repaid them within weeks" and that Joe Biden "had no information at all about the source of the funds I used to repay him."

"The complete explanation is that Joe lent me money, and I repaid him as soon as I had the funds to do so," James Biden said.

James Biden explained that, at times, "because of the episodic nature of the income from my consulting work, there have been a number of occasions when my personal financial obligations have exceeded our available funds."

He did not elaborate on how he used the loans from his brother.

After Comer issued a subpoena for James Biden's testimony last year, his attorney, Paul Fishman, said there was "no justification" for the interview, and reiterated that "Jim Biden has never involved his brother in his business dealings."

Of the loan repayments, Fishman added at the time that "there is nothing more to those transactions, and there is nothing wrong with them."

The Republican investigation was dealt a blow last week when special counsel David Weiss filed felony false statement and obstruction charges against a confidential FBI source who accused President Biden and his son of accepting a $10 million bribe from a Ukrainian oligarch -- an accusation core to Republicans' impeachment case that the Justice Department said is false.

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Other witnesses -- a onetime and tangential business associate of Hunter and James Biden, Tony Bobulinski, and Hunter Biden's former business partner, Devon Archer -- have supported the committee's notion that Joe Biden knew more about his family's business affairs than the president, the White House and other business associates close to the family have let on.

Archer, who collaborated with Hunter Biden on multiple deals, told the committee that while Joe Biden met on a handful of occasions with their foreign business partners and was sometimes put on speakerphone in their presence, none of their discussions extended beyond pleasantries or delved into "commercial business."

Bobulinski went so far as to suggest that James Biden had created a shell company to protect Joe Biden's financial stake in the business deal with the Chinese energy company.

"Joe Biden is not on this document. He didn't sign it," Bobulinski said in his Feb. 13 interview with the committee. "However, I don't know if Joe Biden had an ownership [stake in the shell company] ... I just know that Jim Biden signed on behalf of it."

Instead, Bobulinski, whose credibility has been called into question by Democrats after he coordinated with former President Donald Trump's campaign ahead of the 2020 election, suggested that lawmakers put James Biden "under oath" to reveal "the extent" of Joe Biden's alleged role.

Hunter Biden, who pleaded not guilty in October to federal gun charges and not guilty last month to tax charges, is expected to appear before the panel on Feb. 28.

ABC News' Laura Romero contributed to this report.