The United States said a "controlled shutdown" of the Russian-occupied Zaporizhzhya nuclear power plant in southern Ukraine was the "safest option" and urged Moscow to agree to a demilitarized zone around the site, where increased fighting is sparking fears of a possible massive radiation leak.
"As we've said many times, a nuclear power plant is not the appropriate location for combat operations," White House national security spokesman John Kirby told reporters on August 29.
"We continue to believe that a controlled shutdown of the Zaporizhzhya nuclear reactors would be the safest and least risky option in the near term," he added.
His comments come as a mission from the UN nuclear safety agency is due to arrive in Kyiv late on August 29 and quickly travel on to the Russian-occupied nuclear plant.
SEE ALSO: Ukraine Claims Breakthroughs Made Against Russian Forces In Southern OffensiveIt was not immediately clear if the team would be allowed access to the nuclear site by occupying Russian forces.
Rafael Grossi, head of the International Atomic Energy Agency (IAEA), said in a post on Twitter that the "day has come" and a team of IAEA experts was "now on its way" to the nuclear power plant, which Russian invading forces have controlled since shortly after the Russian invasion began on February 24.
"We must protect the safety and security of #Ukraine's and Europe's biggest nuclear facility. Proud to lead this mission which will be in #ZNPP later this week."
The Ukrainian Foreign Ministry said the IAEA mission was due to reach Kyiv on August 29 and "start work at the Zaporizhzhya nuclear plant in the coming days."
The IAEA's experts were set to assess physical damage to the plant, determine the functionality of safety and security systems, evaluate staff conditions, and perform urgent safeguards activities, the agency said.
SEE ALSO: U.S. Says Non-Proliferation Treaty Strong Despite Russia's 'Cynical Obstructionism'Neither he nor the agency specified when they would arrive at Zaporizhzhya.
Ukraine's Energy Ministry said it would not comment on the IAEA mission trip "for security reasons."
Ukraine's energy ministry said it would not comment on the IAEA mission "for security reasons."
The United Nations and Ukraine have called for a withdrawal of military equipment and personnel from the plant to ensure it is not a target in the conflict.
That message was reiterated on August 29 by Ukrainian Foreign Minister Dmytro Kuleba, adding in comments on a visit to Stockholm that Russia was putting the world at risk of a nuclear accident.
Kuleba said that the IAEA mission will be the agency's "hardest in its history" due to the active combat activities by Russian armed forces and Moscow’s "very blatant" way of trying to legitimize its presence at the facility.
The G7's Non-Proliferation Directors' Group welcomed news of the IAEA's trip and again voiced concerns about the safety of the plant under the control of Russian armed forces.
"We reaffirm that the Zaporizhzhya Nuclear Power Plant and the electricity that it produces rightly belong to Ukraine and stress that attempts by Russia to disconnect the plant from the Ukrainian power grid would be unacceptable," it said in a statement issued on August 29.
SEE ALSO: Satellite Images Pinpoint Fires Near Zaporizhzhya Nuclear Power Plant In UkraineRussia's permanent representative to international organizations in Vienna, Mikhail Ulyanov, said Moscow welcomed the IAEA mission and said Russia had made a significant contribution to the visit, the RIA Novosti news agency reported.
Safety fears at the facility have escalated in recent weeks as Kyiv and Moscow have traded blame for rocket strikes around the facility in the southern Ukrainian city of Enerhodar.
Attacks were reported over the weekend not only in Russian-controlled territory adjacent to the plant along the left bank of the Dnieper River, but along the Ukraine-controlled right bank, including the cities of Nikopol and Marhanets, each about 10 kilometers from the facility.
Ukraine’s atomic energy agency, Enerhoatom, issued on August 28 a map forecasting where radiation could spread from the power plant in the event of an accident, showing that based on wind forecasts for August 29 a nuclear cloud could spread across southern Ukraine and southwestern Russia.
Authorities last week began distributing iodine tablets to residents who live near the Zaporizhzhya plant in case of radiation exposure.
Much of the concern centers on the cooling systems for the plant’s nuclear reactors. The systems require electricity, and the plant was temporarily knocked offline on August 25 because of what officials said was fire damage to a transmission line. A cooling system failure could cause a nuclear meltdown.
Periodic shelling has damaged the power station’s infrastructure, Enerhoatom said on August 27.
The IAEA reported on August 28 that radiation levels were normal, that two of the Zaporizhzhya plant's six reactors were operating, and that while no complete assessment had yet been made, recent fighting had damaged a water pipeline, since repaired.