Monday 15 June 2026

In the first example of United Kingdom National Nuclear Laboratory (UKNNL) delivering on its role set out in the government’s Advanced Nuclear Framework, it has welcomed the signing of two Memorandums of Cooperation (MoC) with Japan Atomic Energy Agency (JAEA) and Rolls-Royce on developing advanced nuclear reactor and fuels technology.

The formal signing ceremony was held at 10 Downing Street on Sunday 14 June during a visit from Japanese Prime Minister Sanae Takaichi.

The new collaboration brings together world-class nuclear expertise from the UK and Japan on Advanced Modular Reactor (AMR) technology, specifically High-Temperature Gas-Cooled Reactors (HTGR), and the Coated Particle Fuel (CPF) these reactors will use.

The Advanced Nuclear Framework in Action
Published by the Department for Energy Security and Net Zero in February this year, the government’s Advanced Nuclear Framework enables any developer to approach UKNNL to discuss how its capabilities can support technology development, validation, and deployment. This is in line with UKNNL’s mission to enable and deliver nuclear outcomes for government and support growth of the UK nuclear sector.

The framework provides a mechanism for private industry to access UKNNL’s capabilities and expertise in support of advanced nuclear technologies in the UK. These MoCs and the underpinning contract with Rolls-Royce is a clear example of the framework delivering results. UKNNL stands in service to the sector, ready to work with others in a similar way.

A New Chapter in a Long Partnership
UKNNL and JAEA’s cooperation on advanced nuclear technology stretches back to a long-standing partnership first established in 2001.Combined with UKNNL’s existing relationship with Rolls-Royce, this new trilateral collaboration builds on these strong foundations.

UKNNL has been contracted by Rolls-Royce to support the development and demonstration of their AMR in the UK. It is this contract which has enabled UKNNL’s role in this new partnership. It is a genuine vote of confidence in the expertise UKNNL has built, and in its ability to support industry in bringing advanced nuclear technologies to deployment.

Julianne Antrobus, CEO of UKNNL, said:
“I’m delighted that UKNNL has strengthened its partnership with Rolls-Royce and JAEA. This matters because of what it means for the UK and beyond. Advanced nuclear technologies have the potential to deliver clean, safe and reliable energy, stimulating economic growth while supporting the decarbonisation of industries that millions of people work in. Getting these technologies deployed is an economic and social opportunity that the UK is well placed to seize.

“The UK government’s Advanced Nuclear Framework exists to give industry a clear route to access the world-class expertise that UKNNL offers. Being contracted by Rolls-Royce to support this vital work is a strong signal that the framework is delivering and that UKNNL is playing its part in bringing the sector together.

“What makes this moment even more significant is its historical resonance. Britain has a proud history, and is a current pioneer, in advanced nuclear technologies. This is a chance to honour that legacy by turning decades of research and international collaboration into real-world deployment.”

Advanced Nuclear Technology: What It Offers
In addition to large-scale electricity generation, HTGRs have the potential to play an important role in meeting the UK’s net zero commitments. They can offer clean, flexible, high quality and high temperature heat and power to a range of industries, including those that are most difficult to decarbonise through other means. They also include passive safety features in the event of an accident, enabling automatic shutdown of the reactor.

Designed for next-generation HTGRs, CPF offers significant safety advantages and exceptional energy efficiency. Just three poppy seed-sized kernels produce the same energy as burning 1kg of coal, and each kernel’s sophisticated layers of ceramic and carbon coating mean it is considered the most robust nuclear fuel to date.

UK Heritage, Global Momentum
The UK has a proud history of innovation in advanced nuclear technologies. The Dragon Reactor, operated from 1965 to 1975, was one of the world’s first reactors to use what is now widely regarded as next-generation nuclear technology. Japan, through JAEA’s High Temperature Engineering Test Reactor (HTTR), has sustained world-leading expertise in this field for decades, and this new partnership is an opportunity to build on that legacy.

UKNNL’s Preston laboratory houses the UK’s only facility for manufacturing CPF kernels and recently received new cutting-edge coating equipment, marking the first time in a generation the UK will produce coated particle fuel at scale.

This new collaboration between UKNNL, JAEA and Rolls-Royce draws on the best of both nations’ capabilities and positions the UK and Japan to lead as global interest in advanced nuclear technology deployment grows.

Lord Vallance, Minister for Science, Innovation, Research and Nuclear, said:
“We are bringing together crucial expertise through our Advanced Nuclear Framework to deliver a golden age of nuclear and boost our energy security.

“These agreements build on Britain and Japan’s proud legacies of leading innovation in nuclear technologies.

“Together with our world-leading laboratories and industry including Rolls Royce, we will speed up the deployment of clean, secure energy, and place the UK and Japan at the forefront of civil nuclear innovation.”

Chris Cholerton, Group President, Rolls-Royce, said:
“Our two agreements with UKNNL and JAEA are a milestone moment for the UK’s nuclear sector. Strengthening existing relationships between our nations and combining our broad nuclear capability, they will enable us to jointly address technical challenges and accelerate the development of Advanced Modular Reactors and their advanced coated particle fuel, to deliver industrial growth, skilled jobs and energy security for our nations.”

Masanori Koguchi, JAEA President, said:
“It is my great pleasure to strengthen our collaboration with the UK, working with our long-term partner UKNNL, and Rolls-Royce, under this Memorandum of Cooperation. I hope that through our expertise in HTGR technologies, this collaboration will lead to their early deployment, a significant step towards net zero.” 

Photo Credit: Rolls Royce