A weakness has been discovered in a French nuclear reactor of the type set to be built at Hinkley in the UK.
France’s nuclear safety regulator told the BBC the flaw in the steel housing the reactor core at the nuclear plant being built in Normandy is “serious”.
He added that unless he was satisfied with the plans to put it right, he could stop the project.
The fault in the French reactor is thought to be a construction fault, not an inherent weakness in the design.
The troubled European Pressurised Reactor (EPR) under construction in France is one of the standard bearers for the next generation of nuclear power plants.
It is of the same design as that planned for Hinkley C in Somerset and its collapse would deliver a major blow to the so called nuclear renaissance.
“It is a serious anomaly affecting a crucial component of the nuclear power plant,” said Pierre-Franck Chevet, President of the French Nuclear Safety Authority (ASN).
“We have observed a bad chemical and mechanical characteristic,” he said.
ASN has ordered the loss-making French state owned reactor manufacturer Areva to conduct a further round of destructive testing on a similar component which will see the 116 tonne pressure vessel head or lid once earmarked for the planned reactor at Hinkley C destroyed in the process.