In an unprecedented request, President Donald Trump on Wednesday said that he and Democratic nominee Joe Biden should be drug tested before their first presidential debate in September. Trump implied that Biden took drugs in March before a debate with Democratic primary challenger Sen. Bernie Sanders of Vermont.

There is no evidence that Biden took drugs before the debate and there is no record of Biden failing a drug test or admitting to taking drugs. 

“We are going to call for a drug test,” Trump told Washington Examiner chief political correspondent Byron York in an Oval Office interview. “It wasn't that he was Winston Churchill, because he wasn't, but it was a normal, boring debate. You know, nothing amazing happened.”

"I don't know how he could have been so incompetent in his debate performances and then all of a sudden be O.K. against Bernie,” Trump continued. 

Trump said his belief that Biden could be taking drugs is based purely on his own observations.

"All I can tell you is that I'm pretty good at this stuff," Trump said. "I look. I watched him in the debates with all of the different people. He was close to incompetent, if not incompetent. And against Bernie he was normal."

The Biden campaign quickly shot back at the allegations.

"We know it’s unbelievable to Donald Trump, but Joe Biden can speak honestly without a shot of truth serum," Andrew Bates, a spokesperson for the Biden campaign, told Fox News. "We’d like to see Trump do the same."

Trump, 74, has frequently attacked Biden’s mental acuity, calling him “Sleepy Joe” and “Slow Joe.”

Many have questioned Trump's mental fitness. In recent months, videos captured him struggling to walk down a ramp and using two hands to hold a water glass.

John Gartner, a psychologist and a former assistant professor at Johns Hopkins University School of Medicine, provided an assessment of Trump in an April 2019 opinion piece in USA Today in which he stated, "if Donald Trump were your father, you would run, not walk, to a neurologist for an evaluation of his cognitive health."