Bernie Sanders and Michelle Obama try to heal wounds in Democratic Party

America's first lady has joined Bernie Sanders to make an impassioned plea for Democrats to get behind Hillary Clinton's bid to be the nation's next president.

Seeking to bridge deep Democratic divides, Mr Sanders endorsed former rival Mrs Clinton as a champion for the same economic causes that enlivened his supporters, signalling it was time for them too, to support her in the campaign against Republican White House candidate Donald Trump.