Watch in full: Tim Kaine and Mike Pence clash in heated vice-presidential debate

VP candidates scramble to defend their running mates in their first and only debate

tim kaine, mike pence

Senator Tim Kaine (L) and Governor Mike Pence (R) during the vice-presidential debate at Longwood University in Farmville, Virginia | Photo: PA Images

Hillary Clinton and Donald Trump's vice-presidential nominees have squared off in an insult-laden, feisty one-off TV debate.

From the very start of the 90-minute clash, Democrat Tim Kaine was on the attack - aggressively challenging Trump's qualifications to be president and criticising the billionaire's tax affairs.

Republican Mike Pence shot back by laying into Clinton's record in office. He accused her of bungling foreign policy and leaving large swathes of the Middle East "literally spinning out of control".

The candidates bickered continually and regularly interrupted each other, prompting debate moderator Elaine Quijano to intervene at one point.

She told them: "The people at home can't understand either one of you when you speak over each other."

Kaine, a senator for Virginia, attacked Trump on several fronts - lambasting the Republican nominee's failure to release his tax returns, and ridiculing him for his poor grasp of tensions between Russia and Ukraine.

Clinton's running mate added: "(Trump) loves dictators. He's got like a personal Mount Rushmore: Vladimir Putin, Kim Jong Un, Moammar Gadhafi and Saddam Hussein."

Kaine also spent a considerable amount of time challenging Pence about Trump's controversial remarks and positions - including the presidential hopeful's demeaning comments about women and questions about Barack Obama's citizenship.

"Trump can't start a Twitter war with Miss Universe without shooting himself in the foot," he told the audience.

Pence, the governor of Indiana, painted Clinton and Kaine as career politicians who wouldn't give Washington the shake-up it needs - and warned their administration would be "more of the same".

Both vice-presidential candidates have had little opportunity to introduce themselves to the American public, with the spotlight for much of the campaign falling on Clinton and Trump - two of the country's most well-known figures.

Last night's debate in Virginia was the only time the two men, both long-serving politicians who are respected by colleagues, will square off with each other on national television.

Donald Trump was live-tweeting throughout the debate from his hotel room, and immediately afterwards wrote: "Mike Pence won big. We should all be proud of Mike!"

Meanwhile, pinned to the top of Clinton's Twitter page was an unflattering description of Pence - branding him as "a divisive, anti-woman, anti-LGBT, anti-worker extremist".