The International Atomic Energy Agency (IAEA) confirmed the arrival of its mission, which according to the agency, was delayed for three hours on the Ukrainian-controlled side of the frontline on Thursday.
The visit by the team of 14 experts from IAEA, including its chief Rafael Grossi, comes at a crucial moment for the plant, which has endured constant shelling and raised fears of a nuclear accident.
Their trip was mired in risk as shelling had broken out on Thursday, with both Russian and Ukrainian officials confirming that the nearby city of Enerhodar had endured a morning of bombardment.
Mortar shelling by Russians forced one of the the plant’s two working reactors to shut down on the same day, Ukraine’s nuclear operator Energoatom said Thursday, while Ukrainian officials accused Russian forces of shelling the IAEA mission’s pre-agreed route to the plant.
The aim of the mission was to assess the “security and the safety situation” and to establish a permanent presence at the plant, which “we believe is indispensable to stabilize the situation, and to get regular, reliable, impartial, neutral updates of what the situation is there,” Grossi said earlier on Thursday.
While at the plant, the team was able to gather “a lot” of information in a few hours and that he was able to see the “key things,” Grossi said, according to a video released by Russian state news agency RIA Novosti.
The IAEA chief was later seen leaving the plant, according to RIA, but IAEA has yet to confirm Grossi’s departure.
It is unclear how the IAEA would establish a longer presence in the facility, and whether Russia would be open to it.
The Russian-installed Governor of occupied areas of Zaporizhzhia told RIA that the mission would inspect operational parts of the plant and visit its reactors on Thursday.
Yevhen Balytskyi added that the mission would stay until September 3. It is not clear how many members of the IAEA inspection team remain at the plant after Grossi’s reported departure.
Ukrainian Energy Minister Herman Halushchenko also suggested several members of the team would stay onsite “for several days.”
Ukraine would be unable to ensure the security of the mission while in the plant, as it is Russian-held, Halushchenko said, stressing that situation around the nuclear facility remains “a mess.”
A prolonged IAEA presence at the nuclear plant would likely help to stave off the possibility of a dangerous nuclear accident. Russia would welcome a permanent IAEA presence at the facility, its diplomat to the agency and other international organizations in Vienna said Wednesday.
Ukraine’s President Volodymyr Zelensky has previously said that he wants the IAEA to help strike a deal that would demilitarize Zaporizhzhia, rather than simply inspect the plant.
Russian Foreign Minister Sergey Lavrov claimed on Thursday that Russia was doing everything it could so that the IAEA mission could safely carry out its work.
Frequent shelling in and around the plant has raised fears about a nuclear accident. Both sides have accused the other of nuclear terrorism, with Ukraine alleging that the Kremlin is using the nuclear plant as cover to protect its troops and launch attacks.
CNN is unable to verify who is responsible for the shelling.
CNN’s Sergio Olmos, Daria Markina, Anastasia Graham-Yooll and Yulia Kesaieva contributed to this report.