Trump threatens Clinton with jail during second US presidential debate

Donald Trump went on the offensive against Hillary Clinton in Sunday night's second televised US presidential debate, after a disastrous weekend for the Republican candidate in which a tape was released appearing to show him condoning and admitting to sexual assault.

Clinton was in a strong position heading into the debate in St. Louis, but Trump put in a defiant display, attacking the former secretary of state for her record in office and accusing her husband of abusing women.

Referring to Bill Clinton, Trump said "there's never been anybody in the history of politics that has been so abusive to women".

When asked about the controversial Billy Bush tapes, Trump denied having ever been involved in sexual misconduct with women, and instead deflected the issue on to other themes such as border control and counter-terrorism.

"I have great respect for women. Nobody has more respect for women than I do," Trump said.

He then promised a federal investigation into his Democratic opponent, if he were to be elected to the White House.

"If I win I am going to instruct my attorney general to get a special prosecutor to look into your situation – there has never been so many lies and so much deception," he warned. Trump added that she "would be in jail" if he was the new president.

The night started off as bitterly as it would continue, as the candidates refused to shake hands on entering the stage.

Clinton also went on the attack against Trump, questioning once again his temperament to lead the country.

"With prior Republican nominees for president, I disagreed with them. Politics, policies, principles … but I never questioned their fitness to serve," she added. "Donald Trump is different."

Various commentators have asserted that the result of the debate was fairly even, with the Republican showing a more measured demeanour throughout.

The New York billionaire is under intense pressure following the weekend revelations, with several leading Republican figures withdrawing their support for him, as Clinton surges ahead in the polls.