'Protection Zone' Around Ukraine Nuclear Plant Urgently Needed, Says IAEA Chief

External power has been restored to the Zaporizhzhia Nuclear Power Plant after operators were forced to rely on diesel generators for the second time in five days amid sustained shelling, but that only underscores the urgent need to establish a "protection zone" around the Russian-occupied facility in southeastern Ukraine, the head of the United Nation's atomic watchdog said Wednesday.

A pair of independent monitors from the International Atomic Energy Agency who have been stationed at Europe's largest nuclear plant since the conclusion of an inspection last month informed IAEA Director-General Rafael Mariano Grossi around 8:30 am ET that the Zaporizhzhia facility had been reconnected to the grid several hours after a missile damaged an electrical substation more than 100 miles north of the site and caused it to go offline.

Calling the situation "precarious," Grossi tweeted: "We need a protection zone as soon as possible."

Hours earlier, before external power had been restored, the IAEA chief said that the "repeated loss of ZNPP's off-site power is a deeply worrying development, and it underlines the urgent need for a nuclear safety and security protection zone around the site."

Although all six nuclear reactors at the Zaporizhzhia plant have been shut down as of last month, a constant supply of electricity is still required to maintain critical safety systems and prevent a calamitous meltdown of the sort that unfolded 36 years ago at Chernobyl, roughly 400 miles away.

Diesel supplies at the Zaporizhzhia facility are limited, Petro Kotin, the head of Ukraine's state-run nuclear operator Energoatom, said Saturday after the site's outside power was cut off due to shelling. The backup generators have an estimated 10 days worth of diesel, so "we are working on logistics to supply more fuel," he said at the time.

External power was restored Sunday before being severed again overnight. Energoatom blamed the latest blackout on Russian strikes, The Associated Pressreported.

"Now more than ever, during these extremely difficult times, a protection zone must be established around the ZNPP."

If the emergency generators run out of fuel, Kotin warned Saturday, "they will stop, and after that there will be a disaster. There will be a melting of the active core and a release of radioactivity from there."

According to AP, Energoatom on Wednesday accused Russian troops of blocking "a convoy carrying additional fuel for the backup equipment."

The latest developments come after Grossi on Tuesday met with Russian President Vladimir Putin in St. Petersburg as part of the IAEA's efforts to prevent a nuclear catastrophe. Grossi also sat down with Ukrainian President Volodymyr Zelenskyy last week in Kyiv.

"The situation in the region around the Zaporizhzhya Nuclear Power Plant and elsewhere has become increasingly dangerous, precarious, and challenging, with frequent military attacks that can also threaten nuclear safety and security," Grossi said in a statement Tuesday. "Now more than ever, during these extremely difficult times, a protection zone must be established around the ZNPP."

"We can't afford to lose any more time," he added. "The stakes are high. We must do everything in our power to help ensure that a nuclear accident does not happen during this tragic conflict, as it could cause even more hardship and suffering in Ukraine and beyond."

The IAEA chief similarly warned at the end of his team's fact-finding mission last month that "we are playing with fire."

U.N. Secretary-General Antonio Guterres recently endorsed the recommendations outlined in the IAEA's latest report on the "seven indispensable pillars for ensuring nuclear safety and security in Ukraine," reiterating his call for Russian and Ukrainian forces to immediately halt fighting near the Zaporizhzhia facility and for both countries to agree to a demilitarized perimeter around the site.

Each nation has accused the other of being responsible for shelling at the site in recent weeks. Experts have repeatedly sounded the alarm about the mounting risk of a far-reaching disaster, pointing out that the Zaporizhzhia plant contains more radioactive waste than was present at Chernobyl when it exploded.

Radioactive contamination from that 1986 nuclear accident in what is now Ukraine left an area of more than 1,000 square miles uninhabitable and led to the illnesses and deaths of potentially hundreds of thousands of people.

"Any damage, whether intentional or not, to Europe's largest nuclear power plant in Zaporizhzhia--or to any other nuclear facility in Ukraine--could spell catastrophe, not only for the immediate vicinity, but for the region and beyond," Guterres said last month. "All steps must be taken to avoid such a scenario."

Just two weeks after the U.N. chief's remarks, a missile hit within 1,000 feet of another Ukrainian nuclear plant held by Russia, raising fears that the ongoing war could spark an immense environmental and public health calamity.

Zaporizhzhia is one of four Ukrainian regions that Putin recently annexed in violation of international law.

"While the nuclear plant has been under Russian control for months, the city of the same name remains under Ukrainian control," AP reported over the weekend. "Putin signed a decree [last week] declaring that Russia was taking over the plant. Ukraine's Foreign Ministry called it a criminal act and said it considered Putin's decree 'null and void.' Ukraine's state nuclear operator, Energoatom, said it would continue to operate the plant."

Paul Dorfman, a nuclear expert at the University of Sussex, told the newspaper on Wednesday that "what we've got here is the weaponization of civil nuclear, perhaps for the first time."

"In an increasingly unstable world," said the long-time critic of nuclear power, "it's important to understand this and what this implies for nuclear worldwide."