The source from CGNPC said the two Chinese companies are likely to hold a stake of more than 30 percent, while the rest will likely be taken by EDF and French nuclear engineering group Areva.

CGNPC - which has been EDF's longstanding partner, along with Areva, in China, in developing the first two new-technology European pressurized reactors in Taishan, Guangdong province - will definitely have a larger stake than CNNC, according to the source.

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Nuclear power 'to fall short of demand'

But the project that has attracted the Chinese investors might not proceed as expected, since foreign media have always questioned Chinese companies' ability to build power plants based on so-called third-generation nuclear technology such as European pressurized reactors and AP1000 technology, developed by Westinghouse.

Last month, the United Nations accused the British government of suspicious actions over plans to develop its first nuclear power station in a generation.

Environmental inspectors warned there were concerns about a lack of openness with neighboring countries, including Ireland, over potential risks posed by the Hinkley Point C plant.

Analysts said the UN's accusations will cast a shadow on the potential deal between the Chinese investors and the UK government.

But a representative of Britain's Department for Energy & Climate Change said in an e-mail interview on Thursday that the UK China Memorandum of Understanding on civil nuclear cooperation "paves the way for investment and participation from Chinese companies in the UK's new build nuclear energy program."

"Nuclear is vital for our energy security now, and we want it to be part of the energy mix in the future," the DECC said. "The UK government has prepared the groundwork for new nuclear power stations through a package of reforms and regulatory measures that remove barriers to investment and give developers confidence."