ABC News(WASHINGTON) — Former Vice President Joe Biden’s campaign is mounting an offensive strategy in the midst of allegations that President Donald Trump attempted to exert pressure on Ukraine against his political rival.

The drumbeat on impeachment has hit a fevered pitch on the Hill, with House Speaker Nancy Pelosi vowing to move forward with an official impeachment inquiry into Trump. Her announcement came just hours after Biden told a gathering of reporters in Wilmington, Delaware that if the president failed to comply with congressional requests impeachment would be “a tragedy of (Trump’s) own making.”

Biden’s messaging on impeachment might seem a shrewd political move for the Democratic presidential front-runner.

However, Biden may now have to carefully navigate the possible fallout as impeachment hearings will likely delve more deeply into conversations about his son, Hunter, and his work in Ukraine as members of Congress mull whether Trump made aid to Ukraine contingent on that country agreeing to investigate Joe Biden and his son.

All of this came to light after a whistleblower filed a report regarding an alleged phone call between Trump and the Ukrainian president discussing the matter.

Trump acknowledged having discussed the former vice president on a call with Ukraine President Volodymyr Zelensky in July, but denied allegations he encouraged Ukraine to investigate the Bidens — arguing it would have been OK if he did. Trump promised to release on Wednesday an unredacted transcript of his phone call with Ukraine’s president.

“I put no pressure on them, whatsoever,” Trump said Monday of the call. “I could have, I think it would have probably possibly have been OK if I did, but I didn’t–I didn’t put any pressure on them whatsoever, you know why because they want to do the right thing and they know about corruption, and they probably know that Joe Biden and his son are corrupt.”

Trump’s accusations of corruption focus on action Biden took as vice president in 2014, when he led the Obama administration’s efforts to root out corruption in Kiev in the wake of the Ukrainian revolution. In this push, Biden called for the dismissal of Viktor Shokin, who had ostensibly been leading an investigation into Burisma, an oil company that had recently added Biden’s son, Hunter Biden, to its board of directors.

Biden has doggedly insisted that his son did nothing wrong, saying “all the reports indicated that not a single, solitary thing was inappropriate about what my son did. He never talked to me. He never talked to anybody in the administration.” And suggestions that Biden’s actions to remove Shokin were done to benefit his son have been undercut by criticism of the prosecutor from several international leaders who said Biden’s recommendation was justified.

Yuriy Lutsenko, Ukraine’s then-prosecutor general, said in May that he had no evidence of wrongdoing by Mr. Biden or his son.

Both Bidens have denied having any in-depth discussions surrounding Hunter’s work with Burisma, and in an interview with New Yorker Magazine back in July, the younger Biden recalled only one conversation with his father on his work, in which Biden seemed to offer only a brief warning.

“Dad said, ‘I hope you know what you are doing,’ and I said, ‘I do,’” he told the magazine.

But the ongoing controversy, fueled by Trump’s consistent repetition of the claims, still presents a potentially politically perilous situation for Biden, a candidate who has made his ability to stand firmly against Trump and defeat him in a general election matchup, a centerpiece of his campaign.

Biden has also sought to draw a bright line between himself as someone who purports to want American government to be “a beacon to other countries around the world” and Trump who he sees as “shredding the United States constitution.”

The Biden campaign, for its part, has taken an offensive strategy in an attempt to keep the focus on the president’s actions.

“I can take the political attacks,” Biden told a gathering of reporters on Tuesday in Wilmington, Delaware. “They’ll come and they’ll go and in time, they’ll soon be forgotten.”

The next phase, as Congress delves into impeachment matters, is critical for Biden, political experts said.

“He must realize that if he doesn’t stand up to Trump right now, if he doesn’t hit forcefully, if he doesn’t show that he’s a good sparring partner, then this argument for why we should select Biden in the primaries goes away,” Wioletta Dziuda, an assistant professor at the University of Chicago Harris School of Public Policy who has studied the effects of scandals on political candidates and parties, told ABC News.

The Ukraine scandal also comes during a critical juncture in the Democratic primary, and at a time where Biden’s rivals for the party’s nomination are looking to expose the front-runner’s potential weaknesses in a matchup against Trump.

“It’s probably more problematic for Biden in the short term than it is in the long term,” ABC News Political Analyst Matthew Dowd said.

Dowd said the concern for Biden is that having to explain this situation could leave questions in voters’ minds about his ability to take on Trump effectively.

“It raises two concerns. One is, is that what is there there? And do we really want to– he’s tried to explain it, and maybe there’s an explanation, but it feels unseemly. That’s one. But two is, it just goes to him — do we really want to take a chance? We really want to defeat Donald Trump, do we really want to put someone up against Donald Trump who was flawed in that way?” Dowd said.

Experts also maintain that legitimate questions remain about Hunter Biden’s role on the board of Barisma given his father’s prominent diplomatic responsibilities at the time.

“If somebody is the point person in a U.S. administration … in a country … and then a company hires the son of that person to be on this board, with no obvious qualifications, that would seem like it sets up a conflict of interest,” Yoshiko Herrera, a political science professor at the University of Wisconsin at Madison who is an expert in Russia and Eurasian policy, told ABC News.

Herrera also pointed out that Hunter Biden is far from the first child of a prominent politician to participate in overseas business dealings, and that Trump’s own children have faced questions about potential conflicts in their business dealings while their father is in office.

“It’s a loophole in our government ethics that the financial activities of adult children are not a matter of reportable public record,” Herrera said. “I think it’s bad judgment on Biden’s part to say, ‘Oh, you know, [Hunter] is an adult, he just does what he wants. And you know, I don’t know anything about it.’ That’s exactly what Trump says about his children. So I think in both cases, it’s a conflict of interest.”

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