Business and energy secretary Greg Clark signed the agreement on his third visit to the country since being appointed in July.
Over the course of his stay he met with the Japanese conglomerates Hitachi and Toshiba, both of which are leading nuclear development consortia in the UK.
“Our partnership with Japan is a clear example of how strategic international relationships can power the economy and create opportunities at home and abroad – an important part of our industrial strategy,” said Clark.
“The potential of this collaboration is to create thousands of highly skilled jobs and create major opportunities for the development of supply chains which can provide British engineering and expertise to the civil nuclear industry around the world.”
Hitachi owns Horizon Nuclear Power, the developer behind the 2.7GW Wylfa Newydd plant on the Isle of Anglesey in Wales. The project will make use of two Advanced Boiling Water Reactors (ABWR) supplied by one of Hitachi’s subsidiaries.
Toshiba has a 60 per cent stake in NuGeneration, which is developing the Moorside plant in Cumbria. Westinghouse, a Toshiba-owned company, will supply three of its AP-1000 reactors for the 3.8GW plant.
The projects are expected to create 20,000 jobs, meet nearly 15 per cent of the Britain’s power needs and bring in around £20 billion of contracts to supply chain companies in the UK.
In addition to new build projects, the agreement between the UK and Japan also covers decommissioning and decontamination, research and development and safety and security practices.