Iran has taken a significant new step toward possible atomic-weapons production, starting work on an assembly line to manufacture a key material used at the core of nuclear warheads, the United Nations atomic agency said in a confidential report Wednesday, raising the stakes in Tehran’s standoff with Washington ahead of President-elect Joe Biden’s inauguration.The International Atomic Energy Agency, in a report for member states viewed by The Wall Street Journal, said Iran has told the watchdog that it has started manufacturing equipment it will use to produce uranium metal at a site in Isfahan in coming months.
Uranium metal can be used to construct the core of a nuclear weapon. Iran hasn’t made uranium metal so far, senior Western officials said. The IAEA said Tehran had given it no timeline for when it would do so. Still, the development brings Iran closer to crossing the line between nuclear operations with a potential civilian use, such as enriching nuclear fuel for power-generating reactors, and nuclear-weapons work, something Tehran has long denied ever carrying out.
Iran’s ambassador to the IAEA, Kazem Gharib Abadi, said Wednesday on Twitter that Iran would produce uranium metal, saying it would allow the development of a new fuel for the Tehran civilian research reactor. Iran has said it would take four to five months to install the equipment to produce a uranium powder from which uranium metal is made.
The Iranian government has moved methodically over the past 18 months to expand its nuclear activities. Since the Trump administration withdrew from a 2015 international accord limiting Iranian nuclear activities and began imposing sweeping economic sanctions, Iran has begun stockpiling more enriched uranium and taken other steps barred under the nuclear deal.
Making uranium metal is also prohibited by the deal, which also involves the U.K., France, Germany, China and Russia.
Mr. Biden has said he wants to resume diplomacy with Iran and is looking for a way to return to the nuclear agreement, which was reached when he was vice president. But reviving the international pact could be complicated politically and for technical reasons, and could face stiffer opposition if Iran conducts nuclear weapons-related work.
Western diplomats say that by taking the recent steps, Iran is seeking leverage to pressure Mr. Biden to move swiftly to drop sanctions on Iran and return speedily to the nuclear accord without laying down any conditions. By threatening major new steps on uranium metal production and scaling back U.N. inspectors’ access to Iran, Tehran could leave Mr. Biden with a difficult choice—a rapid return to the deal or a major confrontation between the U.S. and Iran.
IRAN’S NUCLEAR PROGRAM
After the killing of leading Iranian nuclear scientist Mohsen Fakhrizadeh —in an attack Tehran has blamed on Israel—Iran’s parliament in December called on the government to start enriching uranium up to 20% purity and to begin producing uranium metal within five months if the U.S. doesn’t drop its economic sanctions. Israel has declined to comment on the killing of Mr. Fakhrizadeh. Iran said last week it was starting to produce 20% enriched uranium.
Under the 2015 nuclear deal, Iran had agreed to a 15-year moratorium on uranium and plutonium metallurgical production. Iran was allowed to work on advanced fuel for research reactors, one of the few civilian uses for uranium metal, but only after 10 years.
When enriched to weapons grade of roughly 90% purity, uranium metal plays a central role in atomic weapons, forming the core of the device which, when triggered, sets off a chain reaction that creates the nuclear explosion.