The company building Hinkley Point C nuclear power station near Burnham-On-Sea has this week announced further delays and a £1.35bn setback to its flagship project in France, raising fresh fears over its work in the UK.

State-owned French firm EDF said that its Flamanville nuclear plant in Normandy will now cost €12.4bn due to the expense of fixing 66 faulty welds.

The company also said the plant’s start date will be delayed until the end of 2022. Flamanville was originally projected to cost €3.3bn and to start operations in 2012.

It follows a recent £3bn surge in costs at the Hinkley Point C reactor which EDF is building. The project will be marked at up to £22.5bn, which is £2.9bn more than previously forecast, with overruns paid for by the builder.

Plagued by long delays and cost overruns, the state of EDF’s sites across Europe have stoked fears for Britain’s own nuclear ambitions – and piled pressure on ministers to focus on cleaner, cheaper alternatives such as wind and solar power instead.

Richard Black, director of Energy & Climate Intelligence Unit (ECIU), said this week: “The government needs a plan to get to net zero emissions, so the country will need all sorts of projects to meet its future energy needs.”

“However, it is difficult to plan for this if there are cost overruns and projects get seriously delayed.”