Iran said Tuesday that it would begin enriching uranium to 60 percent purity, which is three times what it is now and much closer to that required to make a bomb, although American officials doubt the country is in has the ability to make a weapon in the near future.
Deputy Foreign Minister Seyed Abbas Araghchi, Iran’s leading nuclear negotiator, gave no reason for the relocation, but it appeared to be retaliation for an Israeli attack on the Iranian nuclear power plant, as well as a strengthening of the Iranian hand in nuclear talks in Vienna.
Sunday’s Israeli attack reduced Iran’s uranium enrichment ability to 60 percent, but it is unclear how long.
Mr Araghchi said Iran informed the International Atomic Energy Agency of its decision in a letter on Tuesday.
Iran also attacked an Israeli-owned cargo ship off the coast of the United Arab Emirates on Tuesday. This was the most recent clash in his shadow maritime war with Israel. The attack was another sign of mounting tension in the region, but is believed to have caused little to no damage.
The uranium enrichment announcement came when American intelligence agencies said that while Iran has gradually resumed nuclear material production since President Donald J. Trump stepped down from the 2015 nuclear deal, there is no evidence that it has resumed operations that was necessary to turn this material into a nuclear weapon.
“We continue to assume that Iran is not currently engaged in the main nuclear weapons development activities that we believe are necessary to manufacture a nuclear device,” the agencies said in their annual threat assessment report released Tuesday.
However, the report states: “Unless Tehran receives sanctions relief” – as Iran has requested – “Iranian officials are likely to consider options ranging from further enriching uranium up to 60 percent to designing and building a new one” Nuclear reactor that could do this. Long-term production of bomb-quality material. That would take years.
The assessment seems to give President Biden some breathing space when negotiations begin in Vienna aimed at restoring some form of the nuclear deal.
But there are still risks: Iran has a long relationship with North Korea, with whom it has exchanged missile technology, and officials have been concerned for years that Iran might try to buy proven nuclear technology from the north.
White House press secretary Jen Psaki called Iran’s announcement “provocative” on Tuesday and said she “questions the seriousness of Iran regarding the nuclear talks”.
Mr Araghchi, who was instrumental in the negotiations on the 2015 nuclear deal between Tehran and the United States, also said on Tuesday that Iran would replace the centrifuges damaged by the attack on the Natanz nuclear power plant on Sunday that have exploded put the system out of operation. He said Iran will install another 1,000 centrifuges there to increase the facility’s capacity by 50 percent.
An Iranian official also re-estimated the damage caused by the attack, saying that several thousand centrifuges were “completely destroyed”. This level of destruction undermines much of Iran’s ability to enrich uranium.
However, the full extent of the damage is unknown and Iran is believed to be vulnerable to further attacks on its nuclear infrastructure. Until the power supply systems in Natanz are rebuilt, it would be impossible to get new centrifuges to turn.
Iran is expected to replace the first generation centrifuges damaged in the Israeli attack with more advanced and efficient models.
Iran has another well-known manufacturing facility, Fordow, which is buried deep in a mountain, but its capacity is limited.
Iran blamed Israel for Sunday’s Natanz explosion, an assessment confirmed by American and Israeli intelligence officials. The Israeli government has not made a public statement.
Mr Araghchi is in Vienna this week for indirect talks with the United States to revive the 2015 nuclear deal. The deal restricted Iran’s nuclear program in exchange for lifting certain sanctions against Iran, and Mr Biden has spoken out in favor of restoring it in some way.
After the United States withdrew from the deal and Mr Trump imposed new sanctions, Iran abandoned its obligations under the deal and increased its uranium enrichment to 20 percent, a level that would have violated the terms of the deal.
Uranium enriched to 60 percent purity would be another breach and is a short step away from bomb fuel, which is typically considered 90 percent or greater in purity. While uranium enriched to 60 percent can be used as fuel in civilian nuclear reactors, such uses have been discouraged worldwide because of the ease with which it can be converted into bomb fuel.
Iran has enriched uranium to a purity of around 20 percent in its Fordow plant, which uses around 1,000 centrifuges.
To increase the level to 60 percent purity, Iran would have to use roughly half of these machines for the new enrichment job. Cleaning to 90 percent would require around a hundred more machines.
In an interview, Olli Heinonen, former chief inspector of the International Atomic Energy Agency based in Vienna, said that Iran could theoretically enrich from 60 percent to 90 percent in a week, compared to a month or so from 20 percent.
“It’s not much of a difference,” he said.
“This is a demonstration at this point,” said Dr. Heinonen that Iran has reached the 60 percent level. “They want to show that they can.”
The much more difficult step, he said, would be converting 90 percent enriched uranium into the core of an atomic bomb.
In yet another possible retaliation for Sunday’s Israeli attack, Iran attacked an Israeli-owned cargo ship, the Hyperion Ray, off the coast of the United Arab Emirates on Tuesday.
According to a person familiar with the details of the voyage, the ship evaded the attack and was not hit. Israeli news media reported that it suffered minor damage.
An Israeli security official said Israel was trying to ease tension in the Persian Gulf region and has no intention of responding with another attack on an Iranian ship.
The Israeli army, the Ministry of Defense and the Prime Minister’s Office declined to comment.
In the past few days, Israel had asked the United States to help protect the ship, an American official said.
Israeli officials were concerned that it could be targeted by the Iranian Islamic Revolutionary Guard Corps in response to Israel’s apparent mine attack on an Iranian military ship in the Red Sea last week, the American official said.
A cargo ship from the same company, the Helios Ray, was attacked by Iran earlier this year.
Iranian officials on Tuesday released more details about the Natanz attack, suggesting the damage was greater than Iran had previously reported.
Alireza Zakani, MP and head of the research center, said on state television that “several thousand of our centrifuges have been completely destroyed,” which is a large part of the country’s uranium enrichment ability.
He described official statements on Monday that the facility would be repaired quickly as false promises.
Foreign intelligence officials said it could take many months for Iran to undo the damage.
Iranian officials were furious at the vulnerabilities that enabled a range of attacks on the Iranian nuclear program over the past year, ranging from sabotage of nuclear facilities to classified information theft to the murder of Iran’s chief nuclear scientist. Most of these attacks were believed to have been carried out by Israel.
Mr Zakani criticized the Iranian security apparatus for being sloppy, saying it enabled spies to “roam free”, which made Iran a “haven for spies”.
He said that in one incident, some nuclear devices at a large facility were being sent overseas for repair and that the devices were packed with 300 pounds of explosives on their return. In another incident, he said, explosives were placed in a desk and smuggled into the nuclear facility.
Iran has long claimed that its nuclear program is peaceful and aimed at energy development. Israel claims Iran had, and may still have, an active nuclear weapons program, and regards the possibility of a nuclear-armed Iran as an existential threat.
The nuclear talks that began last week in Vienna have been delayed because a member of the European Union delegation tested positive for the coronavirus. Talks could resume as early as Thursday if the member tests negative.
Patrick Kingsley, Ronen Bergman and Steven Erlanger contributed to the coverage.