Energoatom - United Kingdom

[Vaka]

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Encryption: Top Secret
Recipient: Andrew Stone, Energy Secretary, United Kingdom Jamie
Sender: Antonivna Kolisnyk, Marketing Director, Energoatom.
Subject: Future Sizewell and Wylfa Projects

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Good Morning Secretary Stone,

We are thrilled to hear of your interest in our VVER-1200 reactor design. The VVER-1200 is our most technologically advance unit currently in our catalog. Its advanced safety features ensure not only the well being of the surrounding area but to the longevity of the unit. They are also a long lasting unit. The design lifespan is 60 years (extendable to up to 80). Now with both of the locations, Sizewell and Wylfa, offering passive cooling thanks to nearby water sources; this will offer lower lifetime operating costs. The VVER-1200 reactor design seems a perfect choice for both locations.

Before we begin, our engineering team has prepared a short list of questions. Once we get the responses back, we will be able to give you a proper timetable and quote regarding the VVER-1200 reactor designs for both locations.

What regulatory adaptations would be required to meet UK nuclear standards?

What timeline does the government foresee for licensing and construction approval?

Would the UK be interested in a long-term civil nuclear partnership with Ukraine?

Which British industries should be integrated into the supply chain? We are assuming that the United Kingdom has the capabilities to enrich the uranium required for these units. We can supply both entrenched and raw uranium if needed however this will require further work with the Ministry of Energy in Ukraine. Also what are your plans for the spent nuclear fuel? This can also be stored in Ukraine but again will require working closely with the Ministry of Energy.

What role does the government see nuclear energy playing in the UK's long-term energy mix? Does the government anticipate additional reactor sites beyond Wylfa and Sizewell in the future?

Would the government consider a two-reactor procurement package to reduce costs?

What remaining concerns would the UK government have before committing to this project?

We are currently in the process of creating mock-ups for both sites. I hope to have them prepared before our next meeting. Thank you for your interest in the VVER-1200 reactor design and I look forward to working closely with you in the future.

Sincerely,

Antonivna Kolisnyk
Marketing Director
Energoatom

 

[Jamie]

GOV.UK

Security Classification: SECRET​

Dear Antonivna Kolisnyk, (Vaka ),

Thank you for your message and for the detailed introduction to the VVER-1200 design. We appreciate Energoatom’s engagement and the thoroughness of your preparations, the United Kingdom Government welcomes the opportunity to explore potential cooperation and looks forward to reviewing the mock-ups for both Sizewell and Wylfa.

Any reactor technology deployed in the United Kingdom must complete the Generic Design Assessment (GDA) process conducted by the Office for Nuclear Regulation (ONR) and the Environment Agency. This process reviews reactor safety, security, and environmental protection standards in depth. While the VVER-1200’s advanced safety systems are noted, certain design adaptations and documentation updates would likely be required to fully meet UK regulatory frameworks and licensing requirements. Our government is committed to ensuring that any new nuclear deployment proceeds efficiently while maintaining rigorous safety standards.

The UK is open to exploring long-term civil nuclear cooperation with international partners, including Ukraine. Such cooperation could include technology exchange, research collaboration, and supply-chain partnerships, subject to regulatory approval and alignment with UK national security and energy policy frameworks. We strongly encourage substantial participation from British industry in any nuclear project undertaken within the UK. Areas likely to involve UK suppliers include advanced engineering, reactor components, civil construction, digital control systems, and nuclear services.

Regarding fuel cycle services, the UK retains domestic capabilities related to nuclear fuel processing and enrichment through established partners within the civil nuclear sector. Fuel supply arrangements would therefore need to be discussed further to ensure compatibility with UK supply security policies. As for spent nuclear fuel, current UK policy anticipates long-term geological disposal within the United Kingdom. Interim storage at reactor sites would be expected, pending the development of a national Geological Disposal Facility. Exporting spent fuel would therefore not currently align with UK policy, though technical cooperation on fuel management could still be explored.

Nuclear energy remains a central component of the United Kingdom’s long-term strategy for achieving secure, low-carbon electricity generation. The government expects nuclear to play a significant role alongside renewables in delivering reliable baseload power.

While Sizewell and Wylfa are key potential locations, the government continues to assess additional sites and technologies as part of its broader energy strategy. The possibility of a two-reactor package is of interest and could potentially provide economies of scale. However, any such arrangement would need to be evaluated alongside financing structures, regulatory considerations, and supply chain capacity. Before the government could commit to a project of this nature, several key factors would require careful review, including:

• Full regulatory approval through the UK’s nuclear safety and environmental frameworks,
• Financing structure and value for money for UK taxpayers and consumers,
• Supply chain resilience and security considerations,
• Fuel cycle arrangements and long-term waste management compatibility with UK policy,
• Integration with the UK electricity grid and long-term energy strategy.

We welcome continued dialogue on these matters and would be pleased to arrange further technical discussions between our respective teams once your preliminary site mock-ups are available.

Thank you again for your engagement. I look forward to our continued cooperation.

Please find below our initial responses to your questions.

Kind Regards,
Andrew Stone
Energy Secretary

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