Unite, which has more than 26,000 energy sector members, says that a standard design is vital to encourage the largest number of bids for the new build nuclear contracts and to give UK industry the opportunity to supply the construction and manufacturing requirements.

The union says that as well as securing thousands of existing jobs, 10,000 additional jobs could be created if the UK regulator licence designs that could be used throughout the world.

Dougie Rooney, Unite’s national officer, said: “The licensing of a new generation of UK nuclear reactors provides UK industry with a fantastic opportunity to say to the world and to UK population that we are applying the highest possible global standards.

“It also sends a powerful message to the commercial world and to UK industry that it is safe for it to invest in new facilities, new product designs, training and jobs. If international standards are applied there’s also a massive export potential here for UK industry to exploit but industry needs the certainty that this licensing will provide.”

Unite wants a maximum of three designs to be licensed by the UK nuclear regulator, the Nuclear Installation Inspectorate (NII), to give UK business and potential vendors the opportunity to invest in long term product development.