President Obama hit back during the foreign policy debate, on Mitt Romney's statement that he had gone on an "apology tour" around the world.

"Nothing Gov. Romney just said is true," said Obama, "starting with this notion of me apologizing. This has been probably the biggest whopper that's been told during the course of this campaign. And every fact-checker and every reporter who has looked at it, Governor, has said this is not true.

"And when it comes to tightening sanctions — look, as I said before, we have put in the toughest, most crippling sanctions ever. And the fact is, while we were coordinating an international coalition to make sure these sanctions were effective, you were still invested in a Chinese state oil company that was doing business with the Iranian oil sector. So I will let the American people decide, judge who is going to be more effective and more credible when it comes to imposing crippling sanctions."