Iran said on January 2 that it plans to enrich uranium up to 20 percent purity at its underground Fordow nuclear facility "as soon as possible," a level far above limits set by an international nuclear accord.
Ali Akbar Salehi, the U.S.-educated head of the civilian Atomic Energy Organization of Iran, offered a military analogy to describe his agency's readiness to take the next step.
"We are like soldiers and our fingers are on the triggers," Salehi told Iranian state television. "The commander should command and we shoot. We are ready for this and will produce [20 percent enriched uranium] as soon as possible."
His comments on January 2 come a day after the International Atomic Energy Agency (IAEA) said that Tehran had revealed its intention in a letter to the UN nuclear watchdog.
"Iran has informed the Agency that in order to comply with a legal act recently passed by the country's parliament, the Atomic Energy Organization of Iran intends to produce low-enriched uranium (LEU) up to 20 percent at the Fordow Fuel Enrichment Plant," the IAEA said in a statement on January 1.
The letter, submitted on December 31, “did not say when this enrichment activity would take place," the IAEA said.
Russia's ambassador to the IAEA, Mikhail Ulyanov, said earlier on Twitter that IAEA chief Rafael Grossi had reported Iran’s letter to the agency’s board of governors.
Iran currently enriches its uranium stockpile up to around 4.5 percent, which is above the 3.67 percent cap imposed by the 2015 nuclear deal but below the 90 percent purity considered weapons-grade.
An increase to 20 percent would shorten Iran’s break-out time to a potential nuclear weapon, if it were to make a political decision to pursue a bomb. The Iran nuclear deal also prohibits Tehran from enrichment at the Fordow facility, buried deep in a mountain to protect against air strikes.
Iran has gradually reduced its compliance with the accord since the United States unilaterally withdrew from the deal in 2018 and started imposing crippling sanctions on Iran.
Following the assassination of top nuclear scientist Mohsen Fakhrizadeh on November 27, Iran’s parliament passed controversial legislation that ordered an immediate ramping up of the country’s uranium-enrichment program to 20 percent and an end to IAEA inspections.
The government led by President Hassan Rohani has opposed the bill, saying it was detrimental to diplomatic efforts and no funds were allocated to implement the law.
Some analysts have suggested that Iran could use parliament's move to gain leverage in future talks with the United States.
The remaining parties to the deal -- China, France, Germany, Russia and Britain -- said on December 21 that they were preparing for a possible return of the United States to the accord after President-elect Joe Biden takes office on January 20. Biden has said he will try to rejoin the deal, which was struck when he was vice president.
Biden has suggested the United States would reenter the deal if Iran complies with the agreement, leaving other issues of concern such as Iran’s ballistic missiles and support for regional proxies to "follow on" agreements.
Iran says its missile program and regional policies are off the table, and has said it would come back into compliance once the United States and the three European countries that signed the deal fulfill their end of the agreement by providing Tehran with the economic relief promised under the accord.
Tehran has always denied pursuing nuclear weapons, saying its nuclear program was strictly for civilian purposes.