By JON GAMBRELL, Associated Press

VIENNA (AP) — The head of the United Nations’ atomic watchdog said Wednesday that “the jury is still out” on negotiations between Iran and the U.S. over Tehran’s rapidly advancing nuclear program, but described the continuing negotiations a good sign.

Rafael Mariano Grossi, director-general of the International Atomic Energy Agency, made the comment to journalists attending a weeklong seminar at the agency in Vienna.

Grossi acknowledged one of his deputies was in Tehran on Wednesday. Iranian officials identified the official as Massimo Aparo, the head of the IAEA’s safeguards arm. That’s the division that sends inspectors into Iran to monitor its program, which now enriches uranium up to 60% purity — a short, technical step from weapons-grade levels of 90%.

“For the moment, the jury is still out,” Grossi said. “The fact that they continue to meet … that is an indication of a willingness to come to an agreement.”

The talks seek to limit Iran’s nuclear program in exchange for the lifting of some of the crushing economic sanctions the U.S. has imposed on the Islamic Republic, closing in on a half-century of enmity.

U.S. President Donald Trump has repeatedly threatened to unleash airstrikes targeting Iran’s program, if a deal isn’t reached. Iranian officials increasingly warn they could pursue a nuclear weapon with their stockpile of uranium.

Trump has described Iran as having an American proposal to reach a deal. However, Iran repeatedly has denied receiving such a proposal, including on Wednesday with Mohammad Eslami, the head of the Atomic Energy Organization of Iran.

However, if a deal is reached, Iran might allow the IAEA to have American inspectors on their teams during inspections. Americans represent the largest single nationality of IAEA employees, a 2023 agency report showed.

Before Grossi’s comments to journalists in Vienna, the head of Iran’s paramilitary Revolutionary Guard issued a new warning to the U.S. as the negotiations go on.

“Our fingers on the trigger, we are in ambush and we are waiting,” Gen. Hossein Salami warned. “If they make a mistake, they will immediately receive responses that will make them completely forget their past.”

Despite the tensions, Grossi said that he believed “there’s always a way” to reach a deal between the Americans and the Iranians — even with the disagreement over enrichment. However, he added that any possible deal likely would require a “solid, very robust” IAEA investigation of Iran’s program to understand where it stood after years of Tehran restricting inspectors’ ability to assess it.

Nasser Karimi and Amir Vahdat contributed to this report from Tehran, Iran.

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