US has 'comfortable' ability to monitor Iran program: Moniz

Secretary of Energy Ernest Moniz discusses the preliminary nuclear deal with Iran on April 6, 2015.
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The United States would have enough time under a framework agreement to intervene should it detect Iran is using its nuclear program for military purposes, U.S. Energy Secretary Ernest Moniz said on Thursday.

"For a considerable time period, 10 years at a minimum, we will have I would say a very comfortable ability to detect any military activity related to the nuclear program and we would have adequate time to respond. Then over time we still have very strong constraints going forward," he told CNBC's "Squawk Alley."

Moniz, a nuclear physicist, served as the chief expert for the U.S. diplomatic team during negotiations with Iran and five other world powers in Switzerland. The parties reached a tentative deal to curb Iran's nuclear program on April 2, paving the way for Western countries to lift sanctions on the country.

The draft agreement gives the west "unprecedented access" to the program, which will be critical for Iran to earn the confidence of the international community as they pursue a peaceful nuclear program, Moniz said.

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Under the terms of that agreement, Iran and the so-called P5+1 countries would take steps to lengthen to one year the time it would take Tehran to acquire enough material to build a bomb. That provision would last for 10 years.

Iran's negotiators, led by Foreign Minister Mohammad Javad Zarif, also agreed to reduce and cap its installed centrifuges used to enrich nuclear material, limit the level to which it enriches uranium and cut down its stockpiles of low-enriched uranium.

The reduction in uranium stocks represents "literally a 97- to 98-percent reduction from where they will be at the end of June," Moniz said.

He continued to say, "The idea is that in the very long term, Iran hopefully will perform, will prove that it's a peaceful program, but even then as we go to 25 years, we will have access in a completely unprecedented way to their uranium supply chain."

Iran would also be committed "essentially forever" to a measure called the additional protocol, a set of commitments to verification that Moniz said goes beyond the safeguard agreements that international inspectors have in any country.

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Since the draft agreement was reached, Iranian President Hassan Rouhani has demanded that all sanctions be lifted immediately after a deal is done, or Tehran could walk away from the table. Meanwhile, his American counterpart President Barack Obama, has faced criticism from Congress and last week agreed to allow lawmakers to review the accord.

Fact sheets issued by U.S., Iranian, and European diplomats have also contradicted one another on some key points of the framework as the parties attempt to sell a deal to their respective nations.

The P5+1 and Iran face a June 30 deadline for reaching a final agreement.