Britain's nuclear expansion plans have been boosted after Japan's Hitachi signed a £700 million deal that will enable it to start building the next generation of power plants.
The engineering giant is buying Horizon Nuclear Power, which has the rights to build reactors at Wylfa on Anglesey, North Wales, and Oldbury in Gloucestershire, from its German owners E.ON and RWE npower.
In what it described as the start of a 100-year commitment to the UK, Hitachi confirmed that it intends to progress Horizon's plans to build between two and three new nuclear plants at each site.
The facilities, which could be feeding electricity into the national grid in the first half of the 2020s, are expected to generate power equivalent to up to 14 million homes over 60 years.
Up to 6,000 jobs are expected to be created during construction at each site, with a further 1,000 permanent jobs at both locations once operational.
Hitachi has also signed supply chain deals with UK engineering firms Rolls-Royce and Babcock International and has also pledged to establish a module assembly facility in the UK.
The Horizon venture, which currently employs around 90 people, was set up in 2009 as part of the drive to meet the UK's carbon reduction goals.
But RWE and E.ON put the business up for sale in March after Germany's move to abandon nuclear power in the wake of Japan's Fukushima disaster.
Hitachi plans to employ its advanced boiling water technology, which is already in use in four reactors in Japan having been built to time and budget.
Prime Minister David Cameron said Hitachi's involvement represented a "decades-long, multibillion-pound vote of confidence in the UK". Energy and Climate Change Secretary Ed Davey said: "Hitachi bring with them decades of expertise, and are responsible for building some of the most advanced nuclear reactors on time and on budget, so I welcome their commitment to helping build a low- carbon, secure-energy future for the UK."