Donald Trump knew the coronavirus was "5 times more fatal than a strong flu," but he downplayed it so as not to panic.
The US president himself admits it after the release of Bob Woodward's book.
"He lied to the Americans," Biden attacks him.
But the tycoon replies: "He had had my statements for many months. If he thought they were so wrong or so dangerous, why didn't he immediately go public to save lives? Didn't he have an obligation to do so? No, because he knew they were correct and adequate ".
Trump also revealed to Woodward the existence in the US "we have a weapon that no one has ever had, something that Putin and Xi have never known about".
Experts are wondering what could be the unprecedented weapon evoked by the tycoon, who in the past, however, boasted of new publicly known weapons, even if he had revealed previously unknown details.
In February, the Pentagon revealed the existence of a new nuclear warhead installed for the first time, following news that it had been placed on a submarine in late 2019.
In May, however, Trump had heralded a "fabulous" missile that could travel 17 times faster than anything else in the US arsenal.