US Democrats formally nominated Joe Biden for the 2020 US presidential candidate on the second night of the party's national convention.

Biden, a three-time presidential candidate, contesting the election for the top post — more than three decades after his first White House bid.

“It is the honor of my life to accept the Democratic Party’s nomination for President of the United States of America,” Biden said in a tweet. 

Biden is fighting unprecedented logistical challenges to deliver his message during an all-virtual convention this week as the coronavirus epidemic continues to claim hundreds of American lives each day and wreaks havoc on the economy.

The former vice president was becoming his party's nominee as a prerecorded roll call vote from delegates in all 50 states airs, and the four-day convention will culminate on Thursday when he accepts that nomination inside a mostly empty Delaware convention hall. 

His running mate, California Sen. Kamala Harris, will become the first woman of color to accept a major party's vice presidential nomination on Wednesday.

Source: Agencies