(Bloomberg) -- Ukraine said its workers at the Russian-occupied Zaporizhzhia Nuclear Power Plant were told they’ll need to re-apply with Rosatom to keep their jobs. 

President Vladimir Putin’s plan to recognize the Zaporizhzhia region of Ukraine as part of Russian territory is overshadowing international attempts to de-escalate fighting around Europe’s biggest nuclear power station. 

Kyiv’s ambassador told a meeting of the International Atomic Energy Agency on Thursday that Rosatom has sent more officials to Zaporizhzhia to enforce a change in ownership once the Kremlin annexes the territory. 

“These representatives of Rosatom stated that at that moment Zaporizhzhia Nuclear Power Plant will belong to Rosatom and therefore within two weeks all employees must write an application for Rosatom,” Ambassador Yevhenii Tsymbaliuk said. “We call on the IAEA to say a firm no.”

Allowing Russia to claim ownership of Zaporizhzhia would represent the biggest nuclear theft in history. The plant, with six reactors that produce about a fifth of Ukraine’s electricity when operational, would cost at least $40 billion to replicate. Russian forces targeted the facility during the first week of the war and have been there ever since. 

Russia’s Ambassador to the IAEA, Mikhail Ulyanov, suggested that the plant’s transfer to Russian ownership will be beneficial to the employees. Russia and Rosatom had the right of reply on floor at IAEA after Ukraine divulged the news. Neither side used this opportunity.

Russia is “treating Ukraine’s civilian infrastructure as a military trophy, seeking to deprive control over its own energy resources,” said US Ambassador to the IAEA Laura Holgate. 

All of Zaporizhzhia’s reactors are currently shut down, with cooling provided by grid connections to Ukraine’s electricity network. 

The plant “must remain connected to the Ukrainian electricity grid and is an integral part of the Ukrainian energy system,” said Canada’s IAEA Ambassador Troy Lulashnyk, speaking on behalf of more than a dozen countries. 

“Any sham referendum conducted by the Russian Federation within Ukraine’s internationally recognized borders has no political or legal effect on the status of the plant or the areas surrounding the facility,” he said. 

Putin on Friday signed decrees recognizing the “independence” of occupied Kherson and Zaporizhzhia in Ukraine as a prelude to absorbing those regions, as well as Donetsk and Luhansk, into Russia -- a move that’s expected later in the day. 

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