US election 2020: Joe Biden launches presidential bid
Former US Vice-President Joe Biden has declared a presidential bid, putting an end to months of speculation, BBC reported.
In a video announcement, Mr Biden argued that the "core values of the nation... our very democracy, everything that has made America America, is at stake".
The 76-year-old enters a crowded race for the 2020 Democratic nomination.
He is up against 19 other hopefuls, including Senators Elizabeth Warren, Kamala Harris, and Bernie Sanders.
As the source reminds, Mr Biden is the most experienced of the Democratic candidates. A six-term senator, he ran twice unsuccessfully for president - in 1988 and 2008 - and later served as President Barack Obama's deputy for two terms.