Joe Biden secured commanding victories in Michigan and two other states on Tuesday, cementing his position as a frontrunner in the Democratic presidential race.
This puts the former vice president as a challenger for Republican President Donald Trump in the November 3 election.
The next big election milestone begins in a week when 577 delegates are up for grabs.
Speaking in Philadelphia, Biden thanked Sanders and his supporters for their energy and passion. "We share a common goal and together we are going to defeat Donald Trump," he added.
"Winning means uniting America. Not sowing more division and anger."
A candidate needs the support of 1,991 delegates to secure the nomination.
Trump says he is unlikely to order Iran attack if talks progress
Train collision in Egypt’s Giza province kills 7, injures dozens
Saudi coalition says two Houthi missile launchers destroyed in Saada
Saudi energy ministry confirms attempted attack on Aramco building in Riyadh
COP31 climate summit to open in Turkey on Monday
