President Donald Trump is using a new "Presidential Walk of Fame" in the White House to troll his predecessor.

Black and white presidential portraits now hang along the colonnade near the Oval Office in gold frames. But instead of a photograph of former President Joe Biden, there's a picture of an autopen, according to social media posts from the White House and Margo Martin, a special assistant to the president.

Trump has long questioned Biden's mental ability. He has suggested without evidence that aides were signing documents for Biden while he was president by using the autopen, a device that mechanically replicates a signature.

Trump in June ordered an investigation by his White House counsel into autopen use during the Biden administration. The GOP-led House Oversight Committee also is investigating.

In a statement in response to Trump's order, Biden said he "made the decisions about the pardons, executive orders, legislation, and proclamations" during his presidency.

"Any suggestion that I didn’t is ridiculous and false," Biden added. "This is nothing more than a distraction."

Contributing: Bart Jansen, Swapna Venugopal Ramaswamy

This article originally appeared on USA TODAY: Trump trolls Biden with image of autopen as predecessor's White House portrait

Reporting by Zac Anderson, USA TODAY / USA TODAY

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