Final US Presidential Debate

I'll keep you in suspense, okay?'

If Americans entered the debate concerned about what happens the day after this brutally fought election, Trump did little to assuage their fears.

An hour into the 90-minute battle, the Republican nominee was asked whether he would respect the election result and concede if he lost. His answer will go into the history books.

"I'll look at it at the time. What I've seen is so bad," he said, repeating unfounded allegations of vote rigging.

When pressed again he simply said: 'What I'm saying is I'll tell you at the time. I'll keep you in suspense, okay?'

Fellow Republicans rushed to denounce him, and his Democratic rival Hillary Clinton declared herself "appalled" by what she said was an attack on 240 years of US democracy. 

'I never met Putin'

Asked about embarrassing leaked emails, Clinton pivoted to Trump's much scrutinized relationship with Russian President Vladimir Putin and the Republican's refusal to pin the leaks on Moscow.

Clinton suggested Putin wanted a "puppet" in the White House, which prompted a remarkable exchange.

"No puppet. No puppet," said Trump, talking over Clinton. "You're the puppet!"

"No, you're the puppet," he continued.

Composing himself, Trump said "I never met Putin. This is not my best friend. But if the United States got along with Russia, it wouldn't be so bad."

However, Trump has boasted several times in the past of his relationship with Putin, according to PolitiFact.