Calling Donald Trump a "liar" and a man who "doesn't know what he's talking about", Democratic presidential nominee Joe Biden ripped into US president Trump's response to the coronavirus pandemic which has killed more than 200,000 Americans, plunged the economy and upended life across the country.

President Trump and Biden waded into their first debate Tuesday night in Cleveland, Ohio with exactly 35 days until the 2020 US election. In the 90 minute long schedule, Trump's response to the Covid-19 pandemic is expected to remain front and center in this first 2020 presidential debate.