Debates have started in earnest in the United States senate over the Iran Nuclear Deal during its 60-day congressional review period. Secretary of State John Kerry testified before the Senate Foreign Relations Committee, along with Energy Secretary Ernest Moniz, one of the U.S. negotiators, and Treasury Secretary Jack Lew on Thursday. At the hearing it was clear that several Democrats, as well as Republicans, have concerns about the deal. Senate Foreign Relations Committee Chairman Bob Corker, R-Tennessee, went as far to say that John Kerry was "fleeced" on the deal, according to CBS News.

"What I think you've actually done in these negotiations is codify a perfectly aligned pathway for Iran to get a nuclear weapon just by abiding by this agreement," Corker said. "I look at the things that they need to do, the way it's laid out, and I don't think you could more perfectly lay it out. I believe you've been fleeced."

Corker expressed a range of concerns about the deal, ranging from the lifting of conventional arms and ballistic missile embargoes to the potential 24-day lapse before the International Atomic Energy Agency (IAEA) can inspect a site where they suspect unauthorized nuclear development is occurring.

Kerry responded to critics of the deals, saying, "We set out to dismantle their ability to be able to build a nuclear weapon, and we've achieved that."

"Let me underscore, the alternative to the deal we've reached isn't what we're seeing ads for on TV. The alternative to the deal we've reached isn't a better deal - some sort of unicorn arrangement involving Iran's complete capitulation," he added. "That's a fantasy - plain and simple, and our own intelligence community will tell you that."

Kerry was of the opinion that critics of the deal were misleading the public by suggesting a better agreement could have been reached, according to CBS News.

Meanwhile former President Jimmy Carter said it was "improper and a mistake" for Corker to tell Kerry that he had been "fleeced" by Iran.

"I think Corker's comments were improper and a mistake. I think he's wrong about the Iran nuclear deal, I think it's a very good one," Carter said, according to The Tennesean. "I think that anybody that has served in the Senate with John Kerry, or has known him since then as I have ... knows that he's a very astute and wonderful and dedicated person. And if he signs and agreement, I don't have any doubt that it will be carried out."

Kerry prompted the Senators to engage in debate after considering the fact that Iran has had the knowledge and ability to make a nuclear arsenal for over a decade now.

"Folks, they already have what they want. They got it 10 years ago or more," Kerry said. "This isn't a question in giving them what they want. I mean, it's a question of how do you hold their program back?," he asked, according to CNN.