Ukraine has issued a stark warning that Russia is preparing a large-scale assault on its energy infrastructure, specifically targeting networks vital to nuclear power plant safety. Foreign embassies in Kyiv have reportedly raised their highest “red alert” amid fears of imminent strikes that could cause blackouts lasting days in the freezing capital. The warnings come as Ukraine battles a severe winter energy crisis, generating only 11 GW against a demand of up to 18 GW after repeated Russian attacks damaged every power plant since the full-scale invasion began.

First Deputy Prime Minister and Energy Minister Denys Shmyhal disclosed the intelligence in a detailed account of his recent conversation with IAEA Director General Rafael Grossi. Mr Shmyhal noted: “I informed Mr Grossi about the Russians’ preparations for another massive attack against energy infrastructure, with possible strikes on facilities and networks serving nuclear power plants.”

This follows President Volodymyr Zelensky’s Sunday address, in which he warned: “In the coming days we must remain extremely vigilant. Russia has prepared for a strike — a massive strike — and is waiting for the moment to carry it out.”

Ukrainian military intelligence (HUR) has reported reconnaissance activity around critical substations linked to nuclear facilities, with Russia allegedly aiming to disconnect the plants from the grid, deepening blackouts and pressuring concessions in sub-zero temperatures.

Social media reports, including from the widely followed Ukraine Context Telegram channel, claim all foreign diplomatic missions in Kyiv have activated the highest “red” danger level. Diplomats are reportedly instructed to charge backup power sources and stockpile food, water and medicine ahead of a possible bombardment targeting energy infrastructure that could leave the capital without power for three to five days.

While major Western embassies, including the US, have not publicly confirmed a new “red level” directive, the most recent US Embassy security alert from January 8 warned of a “potentially significant air attack” and urged sheltering during air-raid sirens.

The Minister and Mr Grossi agreed on urgent joint measures. Mr Shmyhal stated: “It was agreed to jointly hear the heads of nuclear power plants and IAEA mission leaders working at the facilities in the near future.” They also discussed convening an extraordinary meeting of the IAEA Board of Governors “to assess the consequences of Russian attacks on the Ukrainian power grid.”

Mr Grossi confirmed the IAEA’s response. The Energy Minister added the agency is “preparing a report and methodology for assessing the impact of Russian attacks on the operation of nuclear power plants.” Mr Shmyhal highlighted the “strategic importance” of ongoing IAEA missions at Ukrainian sites, noting a new expert mission is planned for nuclear power plants—including the Russian-occupied Zaporizhzhia facility—and affected substations.

He stressed one firm condition: “It was unacceptable to move the IAEA mission to the temporarily occupied regions of Ukraine through Russian territory.” Mr Shmyhal expressed gratitude for the IAEA’s partnership “in stabilising the situation at Ukrainian nuclear power plants” and for coordination on financing critical energy needs.

The IAEA has repeatedly flagged risks from grid instability. Mr Grossi has warned that “a deterioration of Ukraine’s power grid from persistent military activity has direct implications on the nuclear safety of its nuclear facilities,” including damage to substations essential for sites such as Chornobyl.

Ukraine’s four nuclear plants under government control (Rivne, Khmelnytskyi, South Ukraine) plus the occupied Zaporizhzhia supply a significant share of the country’s electricity. Loss of off-site power could force reliance on diesel generators for reactor cooling, raising accident risks in freezing conditions.

Russian drone and missile barrages continue, with Ukrainian forces intercepting scores overnight, though strikes persist in regions including Kharkiv, Odesa and frontline areas. An energy sector emergency has been declared, with urgent calls for imports and repairs. Lithuania has pledged additional generating equipment, while state firms are required to cover at least half their consumption through imports.

As temperatures drop further, the combination of nuclear-linked threats, diplomatic alerts and acute grid vulnerability heightens international fears of radiological consequences in Europe’s most serious conflict since World War II.