Iran Nuclear Deal, Enriched Uranium, and U.S. Sanctions: Everything You Need to Know

Natasha Bach

Iran is 10 days away from exceeding the uranium stockpile limit imposed by the 2015 nuclear deal.

Behrouz Kamalvandi, a spokesman for Iran’s Atomic Energy Organization, said Monday that the country has quadrupled production of uranium, such that it would surpass the 300-kilogram limit by June 27. He noted, however, that there was “still time” for European countries to step in and protect Iran from U.S sanctions.

The move comes as tensions between the U.S. and Iran are running high, after a number of unexplained bombings of oil tankers in the Persian Gulf, which the U.S. has blamed on Iran. Iran has denied involvement.

Here’s some background on what is happening.

What is the Iran nuclear deal?

In 2015, Iran, the U.S., and a number of other global powers signed the Joint Comprehensive Plan of Action (JCPOA), informally known as the Iran nuclear deal. Under the JCPOA, Iran agreed to limit uranium production and allow international inspectors in the country in exchange for the lifting of preexisting sanctions that were crippling the nation’s economy.

By May 2018, President Donald Trump withdrew the U.S. from the deal. In the months since, the U.S. has reimposed all of its sanctions on Iran.

The other nations have not followed suit, but the deal was weakened. They have nevertheless warned Iran not to violate it, suggesting that they would be forced to reimpose their own sanctions. Iran, for its part, has continued to maintain that its nuclear program is for peaceful purposes.

What is enriched uranium and why is it a big deal?

Enriched uranium can be used for two things: to make reactor fuel and nuclear weapons. The big distinguishing factor is how enriched the uranium is. “Low-enriched” uranium has a lower concentration of U-235 of 3-4% and is used for nuclear power plants. “Weapons-grade” uranium, on the other hand, is 90% enriched.

Under the JCPOA, Iran is required to cap its uranium enrichment at 3.67% until 2030, and the stockpile of this enriched uranium cannot exceed 300 kilograms. These and other limitations were put in place to dramatically decrease Iran’s ability to build a nuclear bomb and increase its “break-out time,” or time needed to rush to make a bomb, to more than one year.

Kamalvandi said that the increased uranium production is to meet the needs for a nuclear power plant in the south of the country, as well as a Tehran research center. However, he said that the enrichment levels needed are 5% and 20%, respectively, which could potentially make it easier and quicker to reach weapons-grade enrichment in the future.

What is really going on here?

After the U.S. withdrew from the JCPOA, it has become more difficult for the remaining countries to mitigate the effects of the reimposed sanctions on Iran’s economy. Some see Iran’s Monday announcement as a means to put pressure on Europe to come up with a solution, as it was timed just ahead of a scheduled meeting of EU foreign ministers in Brussels and the arrival of France’s new ambassador to Iran.

The U.K., Germany, and France have plans to set up an alternative payment mechanism which is intended to help companies trade with Iran, while circumventing penalties from the U.S. But this has not proven sufficient for Iran, which suspended commitments under the agreement last month and gave the remaining signatories to the deal a 60-day deadline to protect it from U.S. sanctions.

In the weeks since, it has largely become a game of chicken: the European countries have threatened to reimpose their own sanctions if Iran resumes uranium enrichment, while Iran has said it would resume such production if the signatories don’t protect it.

Kamalvandi told state TV Monday that “Iran’s reserves are every day increasing at a more rapid rate,” but added that “the move will be reversed once other parties fulfill their commitments.” A U.S. National Security Council spokesperson reportedly called Iran’s plans “nuclear blackmail.”

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