one step closer...,

WaPo | Iran's formal notification Monday to a United Nations nuclear watchdog that it will begin producing higher-grade enriched uranium marks a new and potentially dangerous turn in Tehran's confrontation with the West over its nuclear ambitions.

Iran couched its announcement in terms of a pressing need for fuel at a 41-year-old, U.S.-built research reactor that produces medical isotopes for an estimated 850,000 kidney, heart and cancer patients. But in reality it means that Iran will be a significant step closer to possessing the raw material needed to build a nuclear bomb.

Indeed, Iran does not have the expertise to build the specialized fuel rods needed for the research reactor -- only France and Argentina are expert at it -- so the main consequence of Iran's decision appears to be moving up the enrichment ladder. If Iran tried to fuel the reactor itself, absent international assistance, it would be risky to the reactor and for public safety, according to David Albright, president of the Institute for Science and International Security in Washington.

Iranian officials have acknowledged the difficulty of using homemade fuel. In an interview in December, Mohammad Ghannadi, vice president of the Atomic Energy Organization of Iran, said that while Iran could try to produce the fuel itself, "there would be technical problems. Also, we'd never make it on time to help our patients."

Meanwhile, enriching uranium under the guise of medical needs will get Tehran much closer to possessing weapons-grade material. Iran insists it has no interest in nuclear weapons. But Albright said 70 percent of the work toward reaching weapons-grade uranium took place when Iran enriched uranium gas to 3.5 percent. Enriching it further to the 19.75 percent needed for the reactor is an additional "15 to 20 percent of the way there."

Once the uranium is enriched above 20 percent, it is considered highly enriched uranium. The uranium would need to be enriched further, to 60 percent and then to 90 percent, before it could be used for a weapon. "The last two steps are not that big a deal," Albright said. They could be accomplished, he said, at a relatively small facility within months.