Donald Trump and Joe Biden square off in final debate

The US Presidential debate between Donald Trump and Joe Biden turned nasty with the US President finishing an angry exchange with "You've got to be kidding".

The final presidential debate between Donald Trump and Joe Biden is underway in Tennessee.

Americans go to the polls in just under two weeks, but millions have already voted in what both sides are painting as the most important election in US history.

The second showdown between the US President and his Democratic rival is being held at Nashville's Belmont University.

The topics selected by moderator Kristen Welker are “Fighting COVID-19”, “American Families”, “Race in America”, “Climate Change”, “National Security” and “Leadership”.

But Mr Trump has vowed to hammer his opponent on revelations of his son Hunter Biden's business dealings.

Welker will be armed with a mute button, after the Commission on Presidential Debates changed the rules following last month's chaotic shouting match.

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