The facility is expected to cost at least £20bn and generate energy at a more expensive price when compared to renewables such as wind and solar. However, it would offer baseload capacity for the grid, which the latter do not.

The project is planned to commence before 2024, with construction taking between nine and 12 years, depending on developments at the oft-delayed and over-budget Hinkley Point C nuclear power station.

French energy giant EDF, which also holds a major stake in Hinkley, initially owned an 80 per cent share in the Sizewell C project, with the state-owned China General Nuclear Power Group funding the remaining 20 per cent.

But last year, security concerns about China caused the government to buy CGN out of the development for just over £100m, meaning it is now co-owned by EDF and the UK government on a 50/50 split basis.

The search for outside investors could help to reduce the financial burden of the project for the government. It is...