Eugene Kaspersky is a buccaneering figure, proud of his achievements in building a thriving anti-virus firm over the last 20 years and never shy about giving his opinions at industry conferences.

But now the firm he founded has to face up to a crisis in a key market after the Trump administration banned the use of his products by US government agencies

When we spoke to him, he seemed to think that his company was the victim of a smear campaign: "Someone is using this situation, turning their aggressive PR against my company."