DUBAI — Iran's supreme leader on Wednesday dismissed initial offers at talks in Vienna to save Tehran's tattered nuclear deal as "not worth looking at," taking a hard-line approach after an attack on the country's main nuclear enrichment site.
The comments by Ayatollah Ali Khamenei, who has final say on all matters of state in the Islamic Republic, come as informal talks in Vienna continue ahead of a planned formal round of negotiations.
The talks already have been thrown into disarray by a weekend attack on Iran's main Natanz nuclear enrichment site suspected to have been carried out by Israel. Tehran retaliated by announcing it would enrich uranium up to 60 percent — higher than it ever has before but still lower than weapons-grade levels of 90 percent.
"The offers they provide are usually arrogant and humiliating (and) are not worth looking at," the 81-year-old Khamenei said in an address marking the first day of the holy Muslim fasting month of Ramadan in Iran.
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While saying he remained positive about Iran's negotiators, he criticized the U.S. and warned time could be running out.
"The talks shouldn't become talks of attrition," Khamenei said. "They shouldn't be in a way that parties drag on and prolong the talks. This is harmful to the country."
Speaking to his Cabinet, an impassioned Iranian President Hassan Rouhani said the first-generation IR-1 centrifuges that were damaged in Sunday's attack would be replaced by advanced IR-6 centrifuges that enrich uranium much faster.
"You wanted to make our hands empty during the talks but our hands are full," Rouhani said.
Rouhani added: "60 percent enrichment is an answer to your evilness. ... We cut off both of your hands, one with IR-6 centrifuges and another one with 60%."
Rouhani also accused Israel of being behind the Natanz attack.
"Apparently this is a crime by the Zionists. If the Zionists take an action against our nation, we will respond," he said, without elaborating.
In Jerusalem at a Memorial Day commemoration, Israeli Prime Minister Benjamin Netanyahu appeared to reference Iran.
"We must never remain apathetic to the threats of war and extermination of those who seek to eliminate us," he said. Israel has not claimed the attack, though it rarely does in its ongoing shadow war against Tehran.
The talks in Vienna are aimed at finding a way for the United States to re-enter Tehran's nuclear agreement with world powers and have Iran comply again with its limits. The accord, which former President Donald Trump unilaterally withdrew the U.S. from in 2018, prevented Iran from stockpiling enough high-enriched uranium to be able to pursue a nuclear weapon in exchange for the lifting of economic sanctions.
Rouhani in his comments Wednesday insisted Iran is still hoping that the Vienna talks lead to a negotiated settlement over its program — and the accompanying lifting of punishing sanctions. Khamenei as well said he believed in his negotiators, but kept up the pressure on the West in his remarks Wednesday night.
"They must do what we say first, and we are assured that it's done, then we will do what is we are required to do," he said.
France, Germany and the United Kingdom, all parties to the nuclear deal, only hours earlier issued a joint statement Wednesday expressing their "grave concern" over Iran's decision to increase enrichment.
"This is a serious development since the production of highly enriched uranium constitutes an important step in the production of a nuclear weapon," the countries said. "Iran has no credible civilian need for enrichment at this level."
Saudi Arabia, a regional rival to Iran, similarly issued a statement, saying enriching at that level "could not be considered a program intended for peaceful purposes."
"The kingdom calls on Iran to avoid escalation and not to subject the security and stability of the region to more tension, and to engage seriously in the current negotiations," Saudi Arabia said.
Iran insists its nuclear program is peaceful, though the West and the International Atomic Energy Agency says Tehran had an organized military nuclear program up until the end of 2003. An annual U.S. intelligence report released Tuesday maintained the American assessment that "Iran is not currently undertaking the key nuclear weapons-development activities that we judge would be necessary to produce a nuclear device."
Iran previously had said it could use uranium enriched up to 60 percent for nuclear-powered ships. However, the Islamic Republic currently has no such ships in its navy.
Iran had been enriching up to 20 percent — and even that was a short technical step to weapons-grade levels.
Officials initially said the enrichment would begin Wednesday. However, an early Wednesday morning tweet from Iran's envoy to the IAEA, Kazem Gharibabadi, suggested it might come later.
He later posted a letter addressed to IAEA Director-General Rafael Grossi warning against "any adventurism by (the) Israeli regime" against Iranian nuclear sites.
"The most-recent cowardly act of nuclear terrorism will only strengthen our determination to march forward and to replace all (damaged) centrifuges with even more advanced and sophisticated machines," Gharibabadi wrote.
IAEA inspectors visited Natanz on Wednesday on their first trip since the sabotage, the agency said, without elaborating on what they found.
The weekend attack at Natanz was initially described only as a blackout in the electrical grid feeding above-ground workshops and underground enrichment halls — but later Iranian officials began calling it an attack.
Alireza Zakani, the hard-line head of the Iranian parliament's research center, referred to "several thousand centrifuges damaged and destroyed" in a state TV interview. However, no other official has offered that figure and no images of the aftermath have been released.