EDF is bracing for a multi-billion euro rise in costs at its Hinkley Point C nuclear site after a fresh evaluation of the project revealed yet another likely delay. An internal review of the troubled project by senior executives at EDF’s French headquarters is expected to confirm fears that the state-backed energy giant will not be able to deliver Hinkley on time or in line with its £18bn budget.

The French newspaper Le Monde reported over the weekend that sources close to the review have said no one believes it can be delivered by 2025.

Instead, the start-up date is likely to be 2027 and pile a further €1bn (£870m) to €3bn euros on to the construction costs of the £18bn project.

The review is being led by Jean-Michel Quilichini, the group’s audit director, and is expected to be made public later this summer.

A UK spokesman for the company declined to comment.

The latest delay is likely to fuel concerns that Government has locked energy bill payers into “a high cost and risky deal” that could fail to deliver on its economic promises.