The United Nations’ atomic watchdog agency said Wednesday its inspectors have confirmed that Iran has begun the production of uranium metal — another violation of the 2015 landmark nuclear deal with world powers.

International Atomic Energy Agency head Rafael Grossi told member nations that his inspectors had confirmed Feb. 8 that a small amount of uranium metal, 3.6 grams, had been produced at Iran's Isfahan plant, the Vienna-based organization said.

Uranium metal can also be used for a nuclear bomb and research on its production is specifically prohibited under the nuclear deal — the so-called Joint Comprehensive Plan of Action — that Tehran signed with Germany, France, Britain, China, Russia and the United States in 2015.

Iran had previously announced the move, saying its plans to conduct research and development on uranium metal production were part of its "declared aim to design an improved type of fuel," according to the IAEA.

Since the unilateral American withdrawal from the deal in 2018, the other members have been working to try and preserve the accord. Tehran has been using violations of the deal to put pressure on the other signatories to provide more incentives to Iran to offset crippling American sanctions re-imposed after the U.S. pullout.

The ultimate goal of the deal is to prevent Iran from developing a nuclear bomb, something it insists it does not want to do. Iran now has enough enriched uranium to make a bomb, but nowhere near the amount it had before the nuclear deal was signed.

The latest move by Tehran further complicates the efforts of the other member nations to entice the U.S. to return to the deal — something President Joe Biden has indicated he would be open to.

When Iran announced its plans in January to produce uranium metal, the German, French and British foreign ministries issued a joint statement saying they were "deeply concerned."

"Iran has no credible civilian use for uranium metal," the nations said, urging Iran to halt the activity. "The production of uranium metal has potentially grave military implications." Iran also recently dismissed a French offer to mediate the nuclear deal.

Although uranium metal in theory can be geared toward generating electricity, experiments with metal alloys are prohibited under the nuclear deal because uranium metal is a key material in the making of nuclear weapons. The process involves converting high-enriched uranium gas into metal that provides the cladding, or outer covering, for the fuel rods that power a nuclear reaction.