A top cyber security official, who was fired by President Donald Trump after saying the 2020 U.S. election was the most secure in history, has branded as "farcical" claims made that the vote was marred by foreign interference.

"All votes in the United States of America are counted in the United States of America," Krebs told 60 Minutes. "I don't understand this claim. All votes in the United States of America are counted in the United States of America. Period."