Iran threatens to break nuclear stockpile limits

That could move nation closer to weapons level

“President Trump has been unambiguous: Iran will not get a nuclear weapon.” Secretary of State Mike Pompeo

WASHINGTON – Iran’s nuclear agency warned Monday that the country was 10 days away from breaking its uranium stockpile limit set under the Iran nuclear deal.

The announcement indicated Iran might leave the agreement reached in 2015 under the Obama administration to curtail Tehran’s nuclear program. The Trump administration abandoned the pact last year. American-led sanctions have mostly excluded Iran from accessing the international banking system, sparking a major economic downturn.

The two countries escalated their rhetoric after two oil tankers were attacked in the Gulf of Oman. The United States blamed Iran for the attacks, but Tehran denied responsibility.

Iran nuclear agency spokesman Behrouz Kamalvandi said Iran quadrupled its production of low-enriched uranium and would increase enrichment levels “based on the country’s needs.” He said Iran needs a level of 5% enrichment for

the nuclear power plant in the southern port of Bushehr and 20% enrichment for a research reactor in Tehran.

Question: How does uranium enrichment work?

Answer: Uranium in the form mined from the earth consists of several uranium isotopes, meaning they have different numbers of neutrons. About 99.3% is the isotope uranium-238 (U-238), and 0.7% is uranium-235 (U-235). U-235 is key for achieving nuclear fission, the process necessary to create nuclear power – or a nuclear weapon.

When arms control experts talk about uranium enrichment, they’re referring to the percentage level of U-235. The goal is to remove unwanted U-238 isotopes from the uranium and increase the proportion of U-235 to a level necessary for nuclear fission.

Iran’s enrichment processes use gas centrifuges, which create a centrifugal force to move the uranium to a higher enrichment level.

Q: What was permitted under the Iran deal?

A: Under the Iran nuclear agreement of 2015, the country was allowed to keep a maximum of 660 pounds (300 kilograms) of uranium enriched to 3.67%. Before the deal, Iran had a much larger stockpile of enriched uranium.

The deal limited the number and type of centrifuges Iran was allowed to have to 5,060 IR-1 centrifuges, which enrich uranium more slowly than newer models.

Q: Why do enrichment levels matter?

A: What concerns experts is that a higher level of uranium enrichment means Iran would be able to begin building a nuclear bomb much more quickly.

Nuclear experts said moving from 20% to 90% enrichment, the level required to build a nuclear bomb, is a much faster process. It would require removing only four more atoms of U-238 per atom of U-235 than it would take to enrich uranium to 20%.

Q: What comes next?

A: The Trump administration has repeatedly said its goal is for Iran to never obtain a nuclear weapon. In a television interview Sunday on Fox News, Secretary of State Mike Pompeo restated America’s goals.

Apart from the deadline of June 27, Iran gave the European Union until July 7 to come up with better terms to keep Iran in the nuclear deal. If the EU fails to do so, according to Iranian President Hassan Rouhani, Iran will resume higher uranium enrichment.