Rep. Ronny Jackson (R-Texas), who served as former President Trump’s White House physician, said Thursday he is circulating a letter among House GOP colleagues that calls on President Biden to take a cognitive test to prove he is mentally fit to be commander in chief.

Jackson began collecting signatures for his letter this week during GOP meetings and House votes. It will be sent to Biden and his team in the next day or two, he said.

“Just everything that has been going on for the last year and a half … [Biden] doesn’t know what’s going on, where he’s at. He’s very confused all the time,” Jackson said in a brief interview with The Hill.

Jackson served as White House physician for both former Presidents Obama and Trump. He’s been attacking Biden’s cognitive abilities since last year’s presidential campaign.

In October, Jackson said he was convinced, based on campaign gaffes, that Biden “does not have the mental capacity, the cognitive ability to serve as our commander in chief and head of state.”

In 2018, Jackson declared that Donald Trump had “excellent” cardiac health, scored a perfect 30 out of 30 on a cognitive test.

Jackson said Trump’s “incredibly good genes, and it’s just the way God made him.”

Biden turned 78 on Nov. 20 and made history this year by becoming the nation’s oldest president.

White House officials said last month that Biden is scheduled to take an annual physical exam “later this year” and will make the results publicly available. They declined to comment Thursday.

In his interview, Jackson pointed out that Trump established a precedent for Biden to take a cognitive test.

“So my point is that President Trump had to submit to that, even when I was his physician. I mean, the precedent’s already been set,” Jackson, a retired Navy rear admiral, told The Hill. “We did it and President Trump did it. And Biden, in his position, and his medical team, need to follow the lead now.”

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