Republican presidential candidate Donald Trump has said he will accept the result of the US election "if I win".
But he added he reserved the right to file a legal challenge.
His comments came after he refused to promise during the final presidential debate in Las Vegas that he would trust the outcome on November 8th if he loses.
The Republican nominee had told the audience he would keep them "in suspense".
Claiming that she had won the third and final presidential debate, Hillary Clinton tweeted a captioned image of herself hugging her daughter Chelsea.
Meanwhile Donald Trump tweeted polls which showed he had won the debate.
ITV News Washington Correspondent Robert Moore believes Hillary Clinton won the debate: "The instant polling that was done at this venue immediately after the debate finished last night would suggest that Hillary Clinton was a clear winner.
"This was probably Donald Trump's best, last chance of changing the central narrative of the campaign, and if anything it was the opposite that occurred."
Donald Trump has refused to say if he would accept the result of the election if he loses, but could he challenge it and what would happen?
During the debate Trump said "bad hombres" needed removing from the US and branded Clinton a "nasty woman". Both sparked jokes on Twitter.
The Republican refused to say whether he will accept the result of the presidential election, saying: "I will look at it at the time."