Washington (CNN) Former Vice President Joe Biden called President Donald Trump an "idiot" for saying Russian interference in US elections is a hoax, the latest barb between the potential 2020 rivals.

The comments from the Democratic presidential candidate came during an interview on CBS' "60 Minutes" in which journalist Norah O'Donnell mentioned Trump's claim that Russian election interference is a "hoax."

"He's an idiot -- in terms of saying that. Everybody knows this. Everybody knows it. Nobody doubts it," Biden said.

The US intelligence community determined that Russia interfered in the 2016 election to hurt Hillary Clinton and help Trump. Despite that, and despite indictments against members of Russian military intelligence for their alleged role in hacking, Trump has publicly sowed doubt about Russian involvement.

Biden and Trump have a lengthy history of exchanging critical and frequently personal words about one another. Their attacks have increased in frequency and vitriol since Biden announced his candidacy and has remained a top tier candidate in the Democratic race for president.

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