Chinese nuclear firms CGNPC and CNNC will also be involved, the source said.
A formal agreement could follow on Monday, the source said. French energy firm Areva will provide the two EPRs or European Pressurized Reactors, the source said, adding that Areva would hold 10 percent take in the project.
The agreed guaranteed price for the electricity provided was 92.5 pounds (€109, $148) per megawatt hour.
According to the source, this is nearly twice the prevailing rate in Britain.
British Energy Minister Ed Davey said over the weekend that London was "extremely close" to sealing a deal with EDF for the first new nuclear power station to be built in the country since 1995.
Negotiations between London and EDF have been dragging for months over the financial terms to build a new nuclear plant at Hinkley Point in Somerset.
They have focused on trying to fix a minimum price for the power supplied as part of a new British policy to reward the production of energy with low carbon emissions.
Britain claims to be the world's oldest civil nuclear power, citing the opening of the first commercial nuclear power facility at Calder Hall in 1956.
Britain's energy ministry, EDF and Areva all declined comment when contacted by AFP.