“But we are close, very close, to cyber terrorism. Perhaps already the criminals have sold their skills to the terrorists – and then…oh, God.”

Speaking privately at the London Cyber Conference, Kaspersky told Sky that he believed that cyber terrorism was the biggest immediate threat to have emerged to confront nations as diverse as China and the US.

“There is already cyber espionage, cyber crime, hacktivisim (when activists attack networks for political ends) soon we will be facing cyber terrorism,” he said.