The Western European powers who are party to the Iran nuclear deal have expressed "grave concern" over Tehran's announcement that it will start enriching uranium up to 60 percent purity.
"Iran's dangerous recent communication is contrary to the constructive spirit and good faith" of ongoing efforts to revive the 2015 agreement, Britain, France, and Germany said in a joint statement on April 14.
Last week in Vienna, Iran and the global powers held what they described as "constructive" EU-hosted talks centered on overcoming an impasse between Washington and Tehran to bring both parties into full compliance with the 2015 nuclear accord, known as the Joint Comprehensive Plan of Action (JCPOA).
Further discussions are scheduled in the Austrian capital on April 15.
Despite the diplomatic efforts, Iran said on April 14 that it will start producing uranium enriched to 60 percent purity by next week following an alleged attack on the country's main Natanz nuclear site that Tehran has blamed on archenemy Israel.
Few details have emerged about the April 11 alleged sabotage attack and no images of the aftermath have been released.
Inspectors from the UN's nuclear watchdog visited the site without commenting on the extent of the damage caused by the alleged attack.
"IAEA inspectors are continuing their verification and monitoring activities in Iran, and today have been at the Natanz enrichment site," the International Atomic Energy Agency said in a statement on April 14.
"The IAEA will continue to report on relevant developments regarding Iran's nuclear program to the IAEA Board of Governors," it added, referring to its 35-nation decision-making body.
Israel is suspected of carrying out sabotage against Iran in the past, including cyberattacks and assassinations of nuclear scientists.
The White House has said it remains committed to talks with Iran despite Tehran's "provocative" statement that it will ramp up uranium enrichment.
Under the nuclear agreement, abandoned by the United States under former President Donald Trump, Iran had committed to keep enrichment to 3.67 percent. Recently it has been enriching up to 20 percent, saying the deal was no longer enforceable.
Enriching uranium to 60 percent would be the highest level achieved by Iran's nuclear program, although it would still be short of the 90 percent purity needed for military use. Tehran has repeatedly denied it is seeking nuclear weapons saying its nuclear ambitions are purely civilian.
Britain, France, and Germany said Tehran's decision was not based on credible civilian reasons and constituted an important step in the production of a nuclear weapon.
"Iran's announcements are particularly regrettable given they come at a time when all JCPOA participants and the United States have started substantive discussions, with the objective of finding a rapid diplomatic solution to revitalize and restore" the accord, the so-called E3 European powers said.
"In light of recent developments, we reject all escalatory measures by any actor, and we call upon Iran not to further complicate the diplomatic process," the statement said.
The pact lifted international sanctions on Tehran in exchange for limits on Iran's nuclear program. But the Trump administration imposed a raft of sanctions on Tehran under a "maximum pressure" campaign after it withdrew from the nuclear agreement in 2018.
Iran responded by gradually breaching many of the nuclear restrictions saying the deal no longer applied.
U.S. and Iranian officials have publicly clashed over the sequencing of possible U.S. sanctions relief and Iran reversing its breaches of the deal.
In a message aimed at Israel, which fiercely opposes the nuclear deal, Iran's President Hassan Rohani said during a cabinet meeting on April 14: "You wanted to make our hands empty during the talks but our hands are full."
Under the agreement, Iran had committed to keep enrichment to 3.67 percent. Recently, it has been enriching up to 20 percent, saying the deal was no longer enforceable.
The White House has said it remains committed to talks with Iran despite Tehran's "provocative" statement that it will ramp up uranium enrichment.
In a message aimed at Israel, Iran's President Hassan Rohani said during a cabinet meeting on April 14: “You wanted to make our hands empty during the talks, but our hands are full."
“We cut both of your hands, one with IR-6 centrifuges and another one with 60 percent,” he added.
IR-6 centrifuges enrich uranium at a far faster rate than the IR-1 first-generation centrifuges that were taken out in the suspected sabotage attack.
On April 13, the IAEA's director-general, Rafael Mariano Grossi, confirmed that Iran had informed the agency that the country “intends to start producing UF6 enriched up to 60 percent."
The White House is "certainly concerned about these provocative announcements," press secretary Jen Psaki told reporters. "We believe that the diplomatic path is the only path forward here and that having a discussion, even indirect, is the best way to come to a resolution."
"We cut both of your hands, one with IR-6 centrifuges and another one with 60 percent," he added.
IR-6 centrifuges enrich uranium at a far faster rate than the IR-1 first-generation centrifuges that were taken out in the sabotage attack.
Rohani reiterated that Tehran is determined to continue negotiations with world powers, and pledged that Iran's nuclear activity will "certainly be peaceful" and remain under IAEA supervision.
Saudi Arabia said on April 14 that enriching uranium to 60 percent purity could not be considered part of a peaceful nuclear program, and called on Iran to avoid escalation and engage seriously in talks with global powers.
Saudi Arabia and other Gulf countries have supported Trump's move to quit the nuclear pact and reimpose sanctions.