The successful lead suppliers – AMEC, Atkins and Cavendish Nuclear – and their supply chains will work with Horizon for the next three years on consultancy and technical design.

The initial focus will be on Horizon’s lead Wylfa Newydd nuclear power station project.

The deal comes as the Government today said it would offer a UK Guarantee to help Horizon and its owners Hitachi deliver the project.

Preliminary site works could get underway from 2015, leading to the start of major on-site work in 2018 and first nuclear construction around 2019.

Chris Ball, Managing Director of Atkins’ Nuclear business, said: “To be selected as a tier one supplier is testament to the success of Atkins’ long standing relationship with Horizon.

“We look forward to further combining our technical expertise, cultural values and local presence in the collaborative development of a sustainable and skilled supply chain to support the successful delivery of Wylfa and Oldbury.”

Clive White, President of AMEC’s Clean Energy Europe business, said: “AMEC has been involved in every single new build programme in the UK, and having the opportunity to partner with Horizon will allow us to support the delivery of nuclear power stations at Wylfa and Oldbury, creating both national and local employment opportunities.”

Horizon chief operating officer Alan Raymant said: “These contracts underline our aspiration to become a leading new nuclear utility company and demonstrate real momentum.

“Working with our new framework suppliers and their supply chains, I‘m confident we will continue to progress our detailed plans as we prepare for our first formal public consultation next year.

“The signing of these contracts also highlights our commitment to working with UK suppliers where possible.”

Suppliers interested in direct opportunities or sub-contracting opportunities should register their company’s information on the Horizon supplier portal.