The project to build Britain's first new nuclear plant in a generation, awarded to a French-Chinese consortium, has been dogged by controversies, with Britain's National Audit Office (NAO) warning on Friday that the government had committed to a "risky and expensive" deal.
EDF said that "a full review of the costs and schedule of the Hinkley Point C project is in progress", as had already been indicated in the company's annual financial report.
The company said the review would be finished "soon" and results would be published when it was completed.
France's Le Monde newspaper on Saturday said the "first conclusions" of the review pointed to building costs overrunning the 21 billion euros budget by one to three billion euros.
The NAO, which audits British public spending, said on Friday that the price guaranteed to EDF under the deal could add an extra €34 billion to energy bills of UK customers.
Critics of the project -- which is expected to provide seven percent of the country's power needs -- have focused on an electricity price guarantee to EDF of €105 for every megawatt hour of power produced by Hinkley for the next 35 years, rising with inflation, despite falling energy prices.
Environmentalists are also strongly opposed, urging the government to instead focus on renewable sources like wind and solar power to meet Britain's future energy needs.