Democratic presidential candidate Joe Biden hit back after being swept up in US President Donald Trump's latest controversy.

Last week, the Washington Post reported that Trump pressured Ukraine's president to investigate a company with ties to Biden's son Hunter. Trump's request seemed designed to elicit damaging information about a rival for the 2020 election.

Biden, the top-polling 2020 candidate who beats Trump in head-to-head matchups in battleground states and nationwide, said that if the President did that, it's only because "he knows I'll beat him like a drum". Biden also challenged Trump to release a transcript of his phone call with the Ukrainian leader.

The scandal includes unfounded accusations spread by Trump and his allies that Biden used his influence as vice-president to help his son with a business deal. Trump and his allies reportedly asked Ukrainian President Volodymyr Zelenskiy to look into Biden's efforts in 2016 to convince Ukraine to fire its top prosecutor, who at the time was also investigating a natural gas company that employed Hunter. Biden said he knew nothing of his son's business deal and was acting on behalf of the US, which saw the prosecutor as ineffective at stamping out corruption.


The Biden campaign sent a memo to reporters listing quotes from news outlets discrediting Trump's attack. The memo seems an effort to keep history from repeating itself. If Trump keeps peddling the story, it could dog Biden's campaign just as Hillary Clinton's emails dogged hers.