With one last chance for both candidates to appeal to millions of voters, Obama was the aggressor from the start of the debate which was mainly devoted to foreign policy issues.
"We're not going to allow Iran to perpetually engage in negotiations that lead nowhere. And I've been very clear to them because of the intelligence coordination that we do with a range of countries, including Israel, we have a sense of when they would get breakout capacity, which means that we would not be able to intervene in time to stop their nuclear program, and that clock is ticking," Obama said.
"We are going to make sure that if they do not meet the demands of the international community, then we are going to take all options necessary to make sure they don't have a nuclear weapon," 51-year-old Obama warned in a live debate.
Taking a harder line, 65-year-old Romney said a nuclear-capable Iran is unacceptable to America, declaring the Islamic republic as "the greatest threat the world faces".
"It presents a threat not only to our friends, but ultimately a threat to us to have Iran have nuclear material, nuclear weapons that could be used against us or used to be threatening to us. It's also essential for us to understand what our mission is in Iran, and that is to dissuade Iran from having a nuclear weapon through peaceful and diplomatic means," he said.
The two candidates agreed that the United States should defend its key ally Israel if Iran attacked Tel Aviv, but Romney said he would tighten sanctions that are already affecting the Iranian economy.
Romney also called for Iranian President Mahmoud Ahmadinejad to be indicted under the UN genocide convention over his comments questioning the Holocaust. The Republican hopeful said he would make sure that Iranian diplomats "are treated like the pariah they are around the world."
"Crippling sanctions were number one. And they do work. You're seeing it right now in the economy. It's absolutely the right thing to do to have crippling sanctions. I'd have put them in place earlier, but it's good that we have them," Romney said, adding there is need to tighten those sanctions.
"I would say that ships that carry Iranian oil can't come into our ports. I imagine the EU would agree with us as well. Not only ships couldn't, I'd say companies that are moving their oil can't, people who are trading in their oil can't. I would tighten those sanctions further," he said.
"We need to increase pressure time and time again on Iran because anything other than a solution which stops this nuclear folly of theirs is unacceptable to America. And of course, a military action is the last resort. It is something one would only, only consider if all of the other avenues had been tried to their full extent," the Republican said.
Responding to questions, Obama denied reports that his administration has agreed to a one-o-one talks with Iran after the elections.
"Those were reports in the newspaper are not true. But our goal is to get Iran to recognize it needs to give up its nuclear program and abide by the UN resolutions that have been in place, because they have the opportunity to re-enter the community of nations, and we would welcome that.
"There are people in Iran who have the same aspirations as people all around the world, for a better life. And we hope that their leadership takes the right decision. But the deal we'll accept is, they end their nuclear program. It's very straightforward," he said.
Both Obama and Romney vowed to support Israel if it is attacked. "I will stand with Israel if they are attacked. This is the reason why, working with Israel, we have created the strongest military and intelligence cooperation between our two countries in history. In fact, this week we'll be carrying out the largest military exercise with Israel in history, this very week. But to the issue of Iran, as long as I'm president of the United States, Iran will not get a nuclear weapon," Obama said.
Romney had a similar view point. "If Israel is attacked, we have their back, not just diplomatically, not just culturally, but militarily. That's number one," Romney said.
"Number two, with regards to Iran and the threat of Iran, there's no question but that a nuclear Iran, a nuclear-capable Iran, is unacceptable to America."
Romney alleged under the Obama administration, Iran has become closer to nuclear weapons. "We're four years closer to a nuclear Iran. And we should not have wasted these four years to the extent they continue to be able to spin these centrifuges and get that much closer," he said.
However, Obama argued that the steps taken by his administration against Iran has yielded results. "Their currency has dropped... Their oil production has plunged to the lowest level since they were fighting a war with Iraq 20 years ago. So their economy is in a shambles," he said.
"The reason we did this is because a nuclear Iran is a threat to our national security and it's threat to Israel's national security. We cannot afford to have a nuclear arms race in the most volatile region of the world. Iran's a state sponsor of terrorism, and for them to be able to provide nuclear technology to non-state actors -- that's unacceptable. They have said that they want to see Israel wiped off the map," he said.
Boca Raton (Florida): US President Barack Obama on Monday warned Iran that the "clock is ticking away" as his Republican challenger Mitt Romney vowed a harder line to prevent Tehran from going nuclear during the last of the three high-stake presidential debates just two weeks before polls.
First Published: Tuesday, October 23, 2012, 11:37