According to a letter reviewed by sources, the US Department of Energy has warned Rosatom, Russia's state-owned nuclear energy firm, not to touch the US-origin nuclear technical data that is export-controlled by the United States Government. The Zaporizhzhia Nuclear Power Plant in Enerhodar contains this sensitive information that could undermine US national security interests.

Despite the plant being operated by Ukrainian staff, Rosatom manages it, and the Energy Department has warned Rosatom that it is "unlawful" for any Russian citizens or entities to handle the US technology. Russian forces continue to control the plant, which raises fears across Europe of a nuclear accident.

The Energy Department's National Nuclear Security Administration has confirmed the authenticity of the letter. It is not clear whether Rosatom has responded to the warning. The Energy Department has also stated that they have no record of any current authorization to transfer this technology and technical data to any Russian national or entity.

The US has been providing support to the Zaporizhzhia plant, but the situation remains delicate, and the warning to Rosatom highlights the US's concern about the sensitive nuclear technology that Russia could potentially access.