Trump fights back after Harris questions whether he is ‘exhausted’

Kamala Harris speaks during a campaign event at in Michigan on Friday (Jacquelyn Martin/AP)

Donald Trump’s energy levels emerged as a flashpoint on Friday as the Republican US presidential nominee and Democrat Kamala Harris scrambled across battleground Michigan with election day looming.

Ms Harris told reporters that Mr Trump was “unfit”, “unstable” and “a danger to our democracy” ahead of an afternoon rally.