Hillary Clinton has said America is in a "make or break" moment with "everything on the line" as the US presidential election goes to the wire.

"Sometimes the fate of the greatest nations comes down to single moments in time," she told her supporters at a rally in Pittsburgh, Pennsylvania.

"This is one of those make or break moments for the United States. It is in your hands."

She added: "And when your kids and your grandkids asked what you did in 2016, when everything was on the line, I hope you'll be able to say, 'I voted for a better, strong, fairer America.'"

The Democrat candidate once again attacked her Republican rival Donald Trump's temperament as unfit for the White House, as ITV News producer in Washington, DC Jamie Roberton reported: