The EU has approved Britain’s ambitious $US26 billion ($A28.13 billion) plan to build its first nuclear plant for a generation, with French and Chinese help, marking a major victory for nuclear energy three years after the Fukushima disaster.
The Hinkley Point project, to be built by France's EDF, had encountered fierce resistance from activists and several member states, but a vote by the bloc's 28 commissioners narrowly approved the deal.
Hinkley Point in southwestern England is one of the world's most ambitious nuclear deals and is seen as a key boost to an industry brought to its knees by the 2011 Fukushima meltdown in Japan.
The EU Competition Commission which led the probe defended its decision, saying that Britain had "significantly modified" its plan in response to concerns raised by Brussels about whether aspects of the deal amounted to state aid.
"On this basis and after a thorough investigation, the Commission can now conclude that the support is compatible with EU state aid rules," EU Competition Commissioner Joaquin Almunia said in a statement on Wednesday.
But Austria has vowed to fight the decision in court, and other member states have voiced concerns that the project makes a mockery of the bloc's stated policy to promote solar and wind power.
Ireland is particularly concerned as the Hinkley Point site is not far from the Irish coast.
The European Commission, the EU's executive arm, launched the probe in late 2013, delving closely into the project's elaborate price guarantee system that critics claim will prove hugely expensive to British consumers for decades to come.
A year ago, the British government signed the huge 16-billion ($26-billion, 18.9-billion-euro) deal for EDF to build two reactors at Hinkley Point C in southwestern England to meet Britain's future energy needs.
Under the accord, EDF gets a 45-50 per cent stake, China General Nuclear (CGN) and China National Nuclear Corporation (CNNC) will have a combined 30-40 per cent and another French firm, Areva, 10 per cent.
Environmentalists see Hinkley Point as an unnecessary use of nuclear energy just when the use of renewables, such as wind and solar power, is beginning to take hold.