Former President Joe Biden took a shot at the authors of a new book that details his alleged cognitive decline during his time in office.

Joe Biden said he “could beat the hell out of” CNN’s Jake Tapper Friday, firing back against the anchor’s new book that painted a damning portrait of his mental capabilities. Biden has faced a fresh onslaught of attacks on his decision to run for president since Original Sin‘s release earlier this month.

Biden said he had no regrets about his decision to seek reelection and was optimistic about his recent cancer diagnosis.