Sen. Rand Paul (R-Ky.) responded on "The Real Story" to President Obama's defense of the Iran nuclear deal, saying he still believes "negotiations are better than war."

Obama pushed back against critics who have argued that the agreement threatens American and Israeli security. 

"The bottom line is this: This nuclear deal meets the national security interests of the United States and our allies. It prevents the most serious threat, Iran obtaining a nuclear weapon, which would only make the other problems that Iran may cause even worse," Obama said.

Gretchen Carlson asked Paul - who has said in the past he would negotiate with Iran - whether he supports the agreement.

"I continue to think negotiations are better than war. But if I were negotiating, I think what we need are negotiations from a position of strength," said Paul. 

Paul said he disagreed with how President Obama went about the negotiations and vowed to vote against it in the Senate. 

He said sanctions on Iran should not have been eased at the start of the talks. Paul also criticized the administration for letting Iran maintain 5,000 centrifuges, "beyond what you would need for a peaceful program."

Paul said Obama seemed to acknowledge that Tehran will not change its behavior in terms of supporting terrorism and funding proxy wars, like in Yemen. 

"If you're going to have an agreement with the Iranians, we need to show that they're going to be significantly changing their behavior," said Paul. 

Watch the interview above.