ATLANTA, June 28, 2024 (BSS/AFP) - Donald Trump challenged US President Joe Biden on Thursday to undergo a cognitive test, saying he did not believe his Democratic rival for the White House in 2024 could pass one.

"I took two tests, cognitive tests. I aced them, both of them, as you know, we made it public. He took none. I'd like to see him take one, just one, a real easy one, like go through the first five questions. He couldn't do it," Trump said during pair's first debate of the election campaign.

Trump has not said what test he took or what his score was, making it difficult to verify his claims.