"We must be absolutely clear about what is true and what is a lie. Here's the truth: A former president of the United States of America has created and spread a web of lies about the 2020 election. He's done so because he values power over principle," Biden said.
"He can't accept he lost," Biden added.
Launching such a direct attack on Trump - though Biden never actually said his predecessor's name during the speech - was a departure for the president, who has spent most of his first year in office focused on pursuing his own agenda rather than looking backward.