Iran offered a last-minute compromise to United Nations' atomic inspectors that stops short of completely curtailing their intrusive monitoring powers, tapping the brakes on a standoff that is escalating to become the Biden administration's first major foreign policy challenge.
The head of the International Atomic Energy Agency ended talks on Sunday in Tehran without convincing Iranian Foreign Minister Mohammad Javad Zarif to roll back a law that will suspend comprehensive snap inspections and other monitoring measures from Tuesday.
IAEA Director General Rafael Mariano Grossi still described the result as "good" and said he won inspectors a three-month partial reprieve which gives the diplomats space to potentially resolve the dispute. "The Additional Protocol is going to be suspended ," Grossi told a news conference in Vienna. "There is less access," he said, adding it was important inspectors would still get information.
Ending all IAEA access under the so-called Additional Protocol could push the standoff closer to a military tipping point by raising suspicions over Iran's nuclear work. Tehran has recently been raising uranium-enrichment levels, installing advanced new equipment and embarking on new fuel-making ventures -- all dual-use activities that have utility for generating nuclear power or crafting a bomb. Iran says its atomic work is for peaceful purposes only.
The Atomic Energy Organization of Iran said in a statement Iran will "record and withhold information" regarding certain activities and monitoring equipment for three months.
"During this period, the IAEA will have no access to this information ... If sanctions are lifted completely within three months, Iran will hand over the information to IAEA, otherwise, the information will be deleted once and for all."
The compromise follows U.S. and European pleas for Iran to continue adhering to the Additional Protocol to give diplomacy a chance. The Biden administration has said it's willing to meet with Iran to discuss a "diplomatic way forward" in efforts to return to the nuclear deal, a first step toward easing tensions. Iran says it will meet with the U.S. if sanctions are removed first.
"It's useful to bridge this gap that we have now," Grossi said. "But for a sustainable situation we will need a political negotiations and that is not up to me."
Iran's willingness to allow unprecedented international monitoring was widely seen by western powers as the most important part of the atomic deal agreed in 2015. Even though Tehran broke enrichment and research covenants in response to Donald Trump's rejection of the accord and imposition of sweeping economic sanctions, it continued to allow broad IAEA safeguards.
Inspectors routinely call snap inspections, monitor uranium mines and visit centrifuge workshops. Special online monitoring tools installed at Iranian enrichment facilities collect and store reams of verification data.
While international monitors will remain in Iran to account for its declared nuclear stockpile, Grossi's failure to extend provisions of the Additional Protocol end the ability for his inspectors to exercise the most rigorous monitoring mechanism ever negotiated.
Earlier on Sunday, Zarif repeated Iran won't discuss the beleaguered accord with the Biden administration until Washington officially rejoins as a participant and lifts Trump-era sanctions on Iran's economy.
Any negotiations with the U.S. would have to address the need for a guarantee that Washington won't quit the deal again, Zarif said.
U.S. national security adviser Jake Sullivan said in an interview with CBS News on Sunday that "it is Iran that is isolated diplomatically now, not the United States, and the ball is in their court."