Iran ratified a law Wednesday to immediately begin enriching uranium to a level closer to weapons grade and to suspend the access of international inspectors to its nuclear facilities if sanctions are not lifted by early February, shortly after President-elect Joe Biden takes office.
The law was the clearest fallout yet from the assassination of Iran's top nuclear scientist.
The law orders Iran's atomic energy agency to begin enriching uranium to 20% immediately, returning the country's enrichment program to the level that existed before the 2015 nuclear agreement.
While converting the entire stockpile could take six months, the order to do so could be seen as a provocation in the waning days of the Trump administration. President Donald Trump made containing Iran a main foreign policy goal of his administration.
The law sets a two-month deadline for oil and banking sanctions against Iran to be lifted before barring inspectors, creating a potential crisis for the early days of the Biden administration. The timing seems intended to press Biden to reenter the nuclear deal with Iran immediately upon taking office.
The speaker of Iran's Parliament, Mohammad Baqer Qalibaf, a former commander of Iran's Revolutionary Guard, said the measure was meant to send the West a message in the aftermath of the assassination that the "one-way game is over."
Iran's parliament, dominated by conservatives, initially passed the legislation in a session Tuesday in which lawmakers expressed anger over the killing of Mohsen Fakhrizadeh, a high-ranking official in the Defense Ministry. Fakhrizadeh was killed Friday in an ambush that Iranian intelligence officials have attributed to Israel.
"The criminal enemy will not feel remorse unless we show a fierce reaction," Qalibaf said. Lawmakers stood up in the chamber with fists in the air, chanting "death to Israel" and "death to America" as they passed the bill.
The law was ratified Wednesday by Iran's Guardian Council, an appointed body that oversees the elected government.
President Hassan Rouhani had opposed the move, calling it counterproductive.
"The government does not agree with this legislation and considers it damaging for diplomacy," he said Wednesday before the law was ratified.
However, his government is now obliged to carry it out.
The order to enrich uranium at 20% would be a concern because it is considered to be close to the threshold of weapons-grade uranium, which can be as high as roughly 90%. Iran has said its nuclear program is for peaceful purposes, though Israeli officials and some American intelligence officials believe that Iran has a secret weapons program.
Iran had limited its enrichment to under 4% under the nuclear agreement, which the Trump administration abandoned in 2018.
The law indicated the higher enrichment was contingent on continued sanctions against Iran and demanded that European nations that are still party to the nuclear agreement provide relief from the U.S. sanctions.
The law also calls for storing 265 pounds per year of uranium enriched to 20% for "peaceful purposes."
The Biden transition team did not comment on the Iranian law.
"We'll decline to comment on this development out of respect for the principle that there is one president at a time," said Ned Price, a Biden spokesman.
Separately, the U.S. government has decided to withdraw some staff members from its embassy in Baghdad through the final weeks of the Trump administration, officials said.
A person familiar with the withdrawal described it as a temporary "de-risking" that will continue into January. The individual spoke on the condition of anonymity to discuss security matters. The number of personnel to be withdrawn was unclear.
The State Department provided no official confirmation of the drawdown but said that ensuring the safety of U.S. government personnel and facilities was its "highest priority."
"The State Department continually adjusts its diplomatic presence at Embassies and Consulates throughout the world in line with its mission, the local security environment, the health situation, and even the holidays," a department official said.
The department official said that U.S. Ambassador Matthew Tueller would remain in Iraq and that the embassy would continue to operate.
Information for this article was contributed by Farnaz Fassihi of The New York Times; and by Louisa Loveluck, John Hudson, Carol Morello, Dan Lamothe and Missy Ryan of The Washington Post.