Biden warns of election-year rhetoric, says ‘it’s time to cool it down’

President Joe Biden sought to calm a divided nation after his rival Donald Trump survived an assassination bid, saying in a rare Oval Office address Sunday it was time to lower the temperature of America's hostile politics.

"You know, the political record in this country has gotten very heated. It's time to cool it down," Biden said in the televised speech, just the third he has given from behind the historic Resolute Desk during his presidency.

As the country reeled from images of a bloodied Trump waving his fist after a gunman opened fire at a rally in Pennsylvania, Biden added that US politics "must never be a literal battlefield, a God forbid, a killing field."