LAS VEGAS: Republican candidate Donald Trump refused to say on Wednesday that he would accept the outcome of the Nov. 8 US presidential election, leaving open the possibility he would challenge the ultimate outcome.

In the third and final presidential debate with Democratic rival Hillary Clinton, Trump said he would wait to decide whether the outcome was legitimate.

"I will tell you at the time, I will keep you in suspense," Trump said.

Clinton responded: "Let’s be clear about what he is saying and what that means: He is denigrating, he is talking down our democracy and I for one am appalled that someone who is the nominee for one of our two major parties would take that position."

In a fiery debate that centered more on policy than did earlier showdowns, Trump accused Clinton's campaign of orchestrating a series of accusations by women who said the businessman made unwanted sexual advances against them.

Trump said all of the stories were "totally false" and suggested Clinton was behind the charges. He called her campaign "sleazy."

"I think they either want fame or her campaign did it, and I think it's her campaign," Trump said.

Clinton said the women came forward after Trump said in the last debate he had never made unwanted advances on women. In a 2005 video, Trump was recorded bragging about groping women against their will.

"Donald thinks belittling women makes him bigger. He goes after their dignity, their self-worth and I don’t think there is a woman anywhere who doesn’t know what that feels like," Clinton said.

"This is a pattern. A pattern of divisiveness, of a very dark and in many ways dangerous vision of our country where he incites violence, where he applauds people who are pushing and pulling and punching at his rallies. That is not who America is," she said.