IRAN ENRICHING URANIUM TO 60% : WHAT DOES IT MEAN?
A highly purified form of uranium is needed to make a bomb, but the intention behind Iran’s push may be to give it leverage in nuclear talks
Iran has started enriching its uranium supply to 60 per cent purity — the closest the country has ever come to the level needed for a weapon — in response to the sabotage of an Iranian nuclear site last weekend linked to Israel. The move by Iran, reported Friday on state media, made good on threats Iranian officials had announced after the sabotage, which have cast a new cloud over talks to save the 2015 deal limiting Iran’s nuclear abilities in exchange for sanctions relief.
President Hassan Rouhani of Iran has gone further, boasting as those talks resumed in Vienna that his scientists could easily enrich uranium to 90 per cent purity — weapons-grade fuel — although he insisted, as Iranian leaders have repeatedly, that Iran “is never seeking to make an atom bomb.”
So what is the significance of uranium’s purity, which is at the heart of the accord that negotiators are trying to rescue? And why is Iran making these claims? Some basic questions and answers:
Uranium contains a rare radioactive isotope, called U-235, that can be used to power nuclear reactors at low enrichment levels and to fuel nuclear bombs at much higher levels. The goal of uranium enrichment is to raise the percentage levels of U-235, which is often done through the use of centrifuges — machines that spin a form of unrefined uranium at high speeds.
Under the nuclear agreement, known as the Joint Comprehensive Plan of Action, c 300 kilograms, or 660 pounds, of uranium enriched to 3.67 per cent for civilian nuclear power. Iran also agreed to stop enriching uranium beyond 5 per cent and to idle hundreds of centrifuges. Its uranium supply fell far below the amount needed to produce even one bomb.
Iran views itself as a boxer in the ring. It is getting punched left and right, without the ability to do damage to the other side. [With the 60 per cent enrichment] Iran’s leaders are trying to resort to any aces they may have.”
Why does Iran have more enriched uranium now?
After then-President Donald Trump repudiated the Iran deal in 2018, reimposed economic sanctions on Iran and added other penalties, Iran undertook a graduated series of steps away from compliance with the deal to retaliate — increasing its 3.67 per cent uranium supply, adding centrifuges, raising uranium purity in some of the supply to 20 per cent and restricting international inspectors’ access to some nuclear sites. All the while, the country said these were easily reversible actions.
What makes the 60 per cent enrichment level particularly threatening is that the tricky process of enrichment becomes far easier and requires fewer centrifuges as it moves into the higher purities. In other words, getting to 90 per cent purity is much easier starting from 20 per cent, and easier still starting from 60 per cent.
Mehrzad Boroujerdi | Iran expert and professor and director of the School of Public and International Affairs at Virginia Tech
How much enriched uranium does Iran now possess?
According to the International Atomic Energy Agency, the nuclear-monitoring arm of the United Nations, Iran as of February had amassed 2,967.8 kilograms of uranium — roughly 14 times the limit under the nuclear accord and theoretically enough to power about three atom bombs if refined to weapons grade. The stockpile includes 17.6 kilograms enriched to 20 per cent — also forbidden under the accord until the year 2030.
Did the sabotage last weekend set back Iran’s ability to enrich uranium?
Almost certainly yes. While Iranian officials have given conflicting accounts of the extent of centrifuge damage at Natanz, the sabotaged enrichment complex, at least one has said that several thousand of the machines were destroyed. But Iran also possesses a second known enrichment site, an underground facility called Fordow, that houses roughly 1,000 centrifuges, and some were deployed early this year to enrich uranium to 20 per cent.
Nuclear experts estimate that to enrich uranium at 20 per cent purification to 60 per cent, Iran would need to devote approximately 500 centrifuges to that job. It would need about 100 more of the spinning machines to further raise the purification level to 90 per cent.
In an interview, Olli Heinonen, a former chief inspector for the International Atomic Energy Agency, said Iran in theory might go from 60 per cent to 90 per cent enrichment in a week, compared with a month or so in moving up from 20 per cent.
“It’s not a huge difference. At this point, this is a demonstration,” he said of Iran’s 60 per cent enrichment threat. “They want to show that they can do it.”
Does this mean Iran could produce a bomb in a week?
No. It is far more difficult, Heinonen and others said, to turn 90 per cent — enriched uranium into the core of an atom bomb. That could take months. And such an estimate does not include the technology, testing and time needed to fit the weapon onto a missile warhead, which could take far longer.
Why would Iran hint at such capabilities?
The threat of militarising its nuclear capabilities has always been a tool of negotiation used by Iran — both in the talks that led to the 2015 agreement and the current negotiations. At the same time, Tehran has made clear that it wants to reach a deal that would end the onerous US sanctions, which severely hamper Iran’s oil sales and international financial transactions. This partly explains Iran’s reluctance to retaliate militarily for attacks on its nuclear sites.
“Iran views itself as a boxer in the ring,” said Mehrzad Boroujerdi, an Iran expert who is a professor and director of the School of Public and International Affairs at Virginia Tech. “It is getting punched left and right, without the ability to do damage to the other side.”
With the 60 per cent enrichment, Boroujerdi said, “Iran’s leaders are trying to resort to any aces they may have.”