The decision means the UK can commit to a long-term package of financial support for the £16bn project.

A so-called “strike price” will be guaranteed to be paid to EDF for 35 years at around £92 per megawatt hour – twice the current market rate.

But EDF still needs to negotiate equity shares with its investment partners, including the Chinese, before the key final investment decision, clearing the way for construction to start.

Sources close to the project said they expected construction to now get underway in early 2015.

Approval for the construction was confirmed today by regulators at the European Commission, following prior approval by Competition Commissioner Vice-President Joaquin Almunia.

The EU examined the bid over concerns the UK Government was giving excess help to the plan.

Almunia said: “After the commission’s intervention, the UK measures in favour of Hinkley Point nuclear power station have been significantly modified, limiting any distortions of competition in the single market.

“These modifications will also achieve significant savings for UK taxpayers.

“On this basis and after a thorough investigation, the commission can now conclude that the support is compatible with EU state aid rules.”