Donald Trump challenged Joe Biden to take a drug test before tomorrow's TV debate - and the Biden campaign gave an equally bizarre response.

The President has repeatedly - without evidence - claimed Mr Biden has relied on "performance enhancing drugs" in previous debates against fellow Democrat Bernie Sanders.

The bizarre line of attack came to a head today, 24 hours before the first Presidential debate of the 2020 US election in Cleveland, Ohio.

The President challenged Biden to a take a drug test ahead of the showdown, saying he would do the same.

I will be strongly demanding a Drug Test of Sleepy Joe Biden prior to, or after, the Debate on Tuesday night. Naturally, I will agree to take one also,” Trump wrote on Twitter.

“His Debate performances have been record setting UNEVEN, to put it mildly. Only drugs could have caused this discrepancy???”

In response, Kate Bedingfield, Biden’s deputy campaign manager treated the President's challenge with every bit of the seriousness it deserved.

“Vice President Biden intends to deliver his debate answers in words. If the president thinks his best case is made in urine he can have at it,” she said.

“We’d expect nothing less from Donald Trump, who pissed away the chance to protect the lives of 200K Americans when he didn't make a plan to stop COVID-19.”

We can't be sure, but we think this might be the first time the word "urine" has been used in an official statement from a major presidential campaign.

The first debate will take place on the 29th September in Cleveland, Ohio.

The debate will be broadcast live on all major news channels from 2am UK time, including BBC News and Sky News, and on CNN which is available on Sky TV in the UK.