To the alarm of environmentalists, a spokesman for EU Competition Commissioner Joaquin Almunia said on Monday that Brussels will "recommend a positive decision" on the Hinkley Point project, reported Agence France-Presse.
"This scandal has to be fought by all legal means possible," Andra Rupprechter told the Kurier daily, adding that he would apply to the European Court of Justice to have the decision annulled.
The Hinkley Point C project, to be built by France's EDF for $26 billion (19 billion euros), is one of the world's most ambitious nuclear deals and is seen as a key boost to the industry.
Brussels launched a probe in late 2013, delving into the project's price guarantee system that critics say will hurt consumers and contradicts London's stated aim of boosting renewable energies.
Together with Austria, which has no nuclear power stations, a number of other countries have also expressed concerns that EU approval would make a mockery of the bloc's stated policy to promote solar and wind power.
The final decision is expected next month, and Rupprechter said that he and EU Commissioner Johannes Hahn, also an Austrian, would do all they can between now and then to change Almunia's mind.