A nuclear power station
The UK’s 16 operational nuclear reactors could be at risk from a foreign drone attackWikimedia Commons

Nuclear power stations in the UK are highly vulnerable to a drone attack, a British nuclear expert has warned.

Nuclear engineer and government adviser John Large said existing power plants are not designed to withstand an attack of "near-cyborg technology" and stressed that the potential security threat is of serious concern, according to The Independent.

In a public address to the French parliament, Large said he set the defences of a standard nuclear power plant against different types of attacks that could be launched by drones, such as the placement of explosive devices and the dispatching of equipment that would aid an insider saboteur.

"In each of the four attack scenarios that I examined, the plant fared very badly indeed," he said.

"If these scenarios had been for real, then there would have been the potential for a major radioactive release."

Large's report follows a number of unexplained flights of tiny unmanned vehicles over nuclear installations in France. The nuclear expert said the serious issues uncovered there are just as relevant to the UK's 16 operational reactors, which generate about 18% of the country's electricity.

Large said that the "flexible access and manoeuvrability of the drones" enables them to easily fly over and twist around reactors that "belong to a different age".

German experts have also warned that drones could identify weaknesses before sending in an attack helicopter to blow apart the thick cement walls of nuclear reactors.

Large urged the UK government to look at his report and assess his findings. British officials have surveyed Large's evidence and forwarded it on to the Office for Nuclear Regulation, but have not requested a copy of the actual report.

Energy Secretary Ed Davey said: "It's unlikely that this report would tell us anything that we haven't already looked at, but anyone that has anything that could help us with our number one priority – safety and security – we would like to see it."

French officials have taken Large's findings very seriously and next month, he will meet France's nuclear and safety regulators and the ministry of defence.

Dr David Lowry, a consultant researcher for the World Institute for Nuclear Security in Vienna, said: "My general view is that all nuclear facilities are at risk of malevolent terrorist attack, but [this] is something that most politicians brush under the carpet."

Last month, two men and one woman were arrested near the Belleville-sur-Loire reactor in the Cher region, south of Paris, after using remote-controlled vehicles in a restricted area within 200m of the plant. They were later released when it emerged that they were merely using model aircraft.