Rafael Grossi, the head of the U.N. nuclear watchdog, traveled to Iran to try and improve oversight of the country’s nuclear activities. However, experts say he faces challenges and must be cautious of empty promises.

In 2018, then-U.S. President Donald Trump withdrew from a nuclear deal with Iran, causing it to unravel. Since then, Iran has increased uranium enrichment and limited cooperation with the International Atomic Energy Agency (IAEA).

Grossi wants more access to Iran’s nuclear facilities. He plans to meet with Iranian officials, including nuclear negotiator Ali Bagheri Kani and Foreign Minister Hossein Amirabdollahian.

Iran is enriching uranium to high levels, which could be used for nuclear weapons. However, Iran has not fully explained some activities to the IAEA and has restricted their access.

Grossi previously secured promises from Iran during a trip in 2023, but little progress was made. The IAEA has lost track of parts of Iran’s nuclear program, raising concerns about secret activities.

Iran has expressed willingness to cooperate with the IAEA, but doubts remain about the outcome of Grossi’s visit. The Biden administration’s approach to Iran adds to uncertainty.

Analysts say Grossi is aware of Iran’s tactics and must push for concrete commitments during his visit.