U.S. Vice-President Joe Biden and Paul Ryan, the Republican vying for his job, went head-to-head in their only televised debate Thursday night, scrapping over a wide range of issues, from foreign policy to abortion.

Biden and Ryan, a congressman from Wisconsin, squared off in Kentucky a week after President Barack Obama’s lacklustre performance in his first debate against rival Mitt Romney.

The debate, moderated by ABC senior foreign affairs correspondent Martha Raddatz, began with a discussion of the Sept. 11 attack on the U.S. Embassy in Benghazi, Libya, which killed Ambassador Chris Stevens and injured several others.

Ryan accused the Obama administration of failing to address requests for extra security in Libya before the attack and then taking days to tell the public that it was a terrorist attack, not the result of a spontaneous protest.

“With all due respect, that’s a bunch of malarkey,” Biden replied.

He said initial information about the Benghazi attack came directly from the “intelligence community,” but they “changed their assessment” later.

On the question of Iran, Ryan said the country has been “racing toward a nuclear weapon” since Obama entered the White House, while Romney has been proposing tough sanctions.

Biden retorted that Iran is already under “crippling” sanctions and very isolated in the international community.

While Iran may be enriching uranium, “they don’t have a weapon to put it into,” Biden said.

“Let’s calm down a little bit.”

Later on in the debate, Biden and Ryan seemed to agree on America’s involvement in Afghanistan, saying it’s time to wind down the U.S. mission in the war-torn country.

Vice-presidential debates usually don’t carry much weight in the overall lead-up to election day, but political observers say the stakes were high this time around.

Many saw the debate as an opportunity for Biden to “avenge” Obama and shift the focus back to the Democratic campaign’s successes before last week’s debate gave Romney the advantage in polls.

Biden took an aggressive approach, often interrupting Ryan mid-argument and calling his rival out on “inaccurate” information.

At one point, a frustrated Ryan said: “I know you’re under a lot of duress to make up for lost ground. But I think people would be better served if we didn’t keep interrupting each other.”

On the home front, Ryan attacked Obama’s controversial stimulus program, particularly spending on green energy programs.

But Biden pointed out that Ryan had asked for stimulus money as a congressman.

Biden also wasted no time bringing up a speech Romney gave to a private gathering, in which he said 47 per cent of Americans simply want government handouts and see themselves as victims.

The speech was secretly recorded and made public.

“I’ve had it up to here with this notion that, ‘Forty-seven percent, it’s about time they take some sort of responsibility here,’” Biden said.

Ryan quipped that Biden “very well knows that sometimes, the words don’t come out of your mouth the right way” -- a jab at the vice-president’s well-known gaffes.

“But I always mean what I say,” Biden shot back.

The rivals also tackled the sensitive topic of abortion. They were asked how their faith -- both men are practising Catholics -- has influenced their views on the issue.

Ryan said he believes that life begins at conception and reiterated Romney’s stance that abortion should only be allowed in cases of rape, incest or when the mother’s life is in danger.

Ryan said the issue should not be left in the hands of “unelected judges.”

Biden said he accepts the Catholic Church’s view on abortion, but refuses to impose it on others.

“I do not believe that we have a right to tell other people, women, that they can’t control their bodies,” he said.

That decision is ultimately between women and their doctors, Biden added.

Obama and Romney will meet for the next presidential debate on Tuesday in Hempstead, New York.

With files from The Associated Press