MUSCATINE, Iowa - Mitt Romney today took a veiled swipe at the current front-runner in Iowa - Ron Paul - during a meet and greet with voters at a local coffee shop here, suggesting that his GOP rival has little concern about Iran obtaining a nuclear weapon.

"At the same time the greatest threat Israel faces and, frankly, the greatest threat that the world faces is a nuclear Iran," Romney said, answering a question about Middle East relations at Elly's Tea and Coffee Shop. "We have differing views on this, some of the people, actually one of the people running for president thinks it's OK for Iran to have a nuclear weapon. I don't."

Romney was clearly referring to Paul, who earlier this month during a debate in Sioux City, Iowa, cautioned against "jumping the gun" when it comes to Iran.

"I would say that the greatest danger is overreacting," Paul said during the Fox News debate. "There is no evidence that they have it. And it would make more sense - if we lived through the Cold War, which we did, with 30,000 missiles pointed at us, we ought to really sit back and think and not jump the gun and believe that we are going to be attacked. That's how we got into that useless war in Iraq and lost so much in Iraq."

But Romney today contrasted his policy with Paul's.

"I don't trust the ayatollahs, I don't trust [Mahmoud] Ahmadinejad," Romney said of the Iranian president.

"I will do everything in my power to assure that Iran doesn't become a nuclear nation [and] threaten Israel, threaten us and threaten the entire world," Romney said.