Republican presidential candidate Rand Paul said on "Lou Dobbs Tonight" that the nuclear agreement with Iran is already off to a troubling start.

The Kentucky senator explained that Iran's supreme leader Ayatollah Khomeini is claiming that the deal will not prevent the Islamic republic from obtaining a nuclear weapon, which is the opposite of what President Obama and Secretary of State Kerry have been saying.

"That's worrisome because we're at the very beginning of the agreement," Paul said. "How do you think this is going to be in a year or two from now?"

He added that the real problem with the deal is that the U.S. and our allies lifted the sanctions on Iran all at once, removing any leverage we had to get a better agreement.

"You wonder about the sincerity of who you're dealing with when they're still calling us this arrogant nation, this great Satan," Paul said. "You have to wonder: Are things really going to change? And if we're acknowledging they're not going to change, should we give up the sanctions so quickly?"

Watch the "Lou Dobbs Tonight" interview above.

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