Iran has come within roughly a month of having enough material to fuel a single nuclear weapon with a nuclear warhead, crossing a threshold that may raise pressure on the United States and its allies to improve the terms of a potential deal to restore the 2015 nuclear agreement.
Experts studying new data contained in reports last week by the International Atomic Energy Agency, the United Nations’ atomic inspection group, say that by enriching nuclear fuel in recent months to near bomb-grade levels, Tehran has gained the capability to produce the fuel needed for a single nuclear warhead within a month or so, under the most extreme timeline.
In April, Iran started enriching its uranium stockpile to 60 percent. It takes far longer to get from low-enriched uranium to 60 percent purity than it does to make the last leap to 90 percent, the level ordinarily used in nuclear weapons. That makes the 60 percent level particularly threatening.
Iran’s supply of 60 percent enriched uranium is not yet sufficient for a weapon. But it has spent the summer installing newer, high-performance centrifuges that could quickly bolster its stockpile.
The fuel must be converted to metal and then into a full nuclear warhead. Those steps would take additional months and perhaps years, depending on technical skill.
On Friday, asked about Iran during a trip to Germany, Secretary of State Antony J. Blinken said that “as time goes on and as Iran continues to make advances in its nuclear program, including spinning more sophisticated centrifuges, enriching more material, learning more, there is a point at which it would be very difficult to regain all of the benefits” of the restrictions Iran agreed to six years ago. “We’re not at that point yet, but it’s getting closer,” he added.