Joe Biden called President Donald Trump "a fool" Tuesday after the president said on "Fox & Friends" that he thought Biden was "taking something" during the Democratic presidential debates.
"He's a fool. The comments were just foolish," Biden said in an interview with NBC affiliate WFLA of Tampa.
Earlier in the day, Trump repeated his calls for Biden to take a drug test ahead of their debate in two weeks in an interview on the Fox News morning show.
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Trump made similar unfounded claims about Hillary Clinton during the 2016 presidential election, when he unsuccessfully challenged her to take a drug test, too, because "I don't know what's going on with her."
During the Fox interview, Trump said he'd thought "something was strange" about Biden during his one-on-one debate with Sen. Bernie Sanders, I-Vt., earlier this year.
Asked whether he thought Biden was taking drugs to "pep himself up," Trump answered: "I do. He's taking something. He's taking something" that "gives him some clarity."
Asked whether it could have been a cup of coffee, Trump said it was maybe "15 cups of coffee."
"I think he should take a drug test," Trump said, claiming, "I would take one, too."
Biden seemed annoyed by the question in the WFLA interview and said, "I'm looking forward to the debate."
"Get ready, Mr. President. Here I come," he said.
The first debate is scheduled for Sept. 29 in Cleveland. There will be three presidential debates and one vice presidential debate.