Shares in EDF have rebounded slightly this morning after falling by nearly 10 per cent yesterday following revelations about problems with welding and components in the firm's nuclear reactors.

The French energy firm, who have one of their main UK bases in Barnwood, announced yesterday that there had been a "deviation from technical standards governing the manufacture of nuclear-reactor components."

That immediately caused concern in the markets and the share price fell from a close of €10.85 on Monday evening to a low of €9.90 at times on Tuesday.

EDF - Électricité de France - is part-owned by the French government and has 58 nuclear power stations in France.

Following their acquisition of British Energy in 2009, they also took over the running of eight nuclear plants in the UK.

They are currently constructing four more nuclear reactors, including two at Hinkley Point C in Somerset.

In their statement, EDF said: "Relating to standards associated with the manufacturing process, the deviation concerns an excursion from temperature ranges in certain areas during manufacturing operations, more specifically involving detensioning heat treatment on some steam generator welds.

"It concerns in-service components as well as new components which have not yet been installed on any sites.

"From the time it was informed of the deviation, EDF - along with Framatome - has been conducting indepth investigations to identify all affected components and reactors, as well as to ascertain their fitness for service."

Shares rebounded slightly on Wednesday morning and were trading up at €10.38 from an opening price of €10.10.