Ukrainian President Volodymyr Zelensky has raised the alarm over what he described as a “critical” situation at the Russian-occupied Zaporizhzhia Nuclear Power Plant, which has been disconnected from the Ukrainian power grid for an unprecedented seven days. In his evening address on September 30, he emphasized that this marks the longest outage since the beginning of the full-scale invasion.

According to Zelensky, the facility - the largest nuclear plant in Europe - is currently operating only on diesel generators to keep its essential safety systems running after Russian attacks destroyed external power lines. He underlined that neither the plant nor its generators were ever intended to sustain such conditions for this length of time, noting that one of the backup generators has already failed.

The president accused Russia of deliberately blocking repair efforts by continuing to shell the area around Enerhodar, the city on the Dnipro River where the plant is located, close to the front line. He warned that such actions posed a threat extending far beyond Ukraine’s borders: “No terrorist in the world has ever dared to do to a nuclear plant what Russia is doing right now.” Zelensky said he has instructed Ukraine’s government and diplomatic corps to urgently raise the issue with international partners.

Moscow, which has controlled the plant since 2022, recently claimed it was supplying emergency power after blaming Ukraine for damage to the grid. While all six reactors have remained offline since Russia’s occupation, the plant still requires electricity to maintain reactor cooling and avert a possible nuclear disaster.

The International Atomic Energy Agency (IAEA) also weighed in. Its director general, Rafael Grossi, confirmed that the agency is maintaining constant contact with both sides in hopes of restoring the connection. He stressed that while the facility is managing for now thanks to its diesel backup systems - described as the “last line of defense” - the reliance on them is not sustainable from a nuclear safety standpoint.

Zaporizhzhia has been at the center of repeated nuclear safety fears since the invasion began, including shelling nearby, chronic power cuts, and staffing challenges under Russian control. The current prolonged outage, Zelensky warned, represents a new and highly dangerous escalation.