In a statement to Reuters, William Evanina, an FBI agent and the director of the US National Counterintelligence and Security Center, warned World Cup travelers that even if they think they are insignificant, hackers could still target them.

“If you’re planning on taking a mobile phone, laptop, PDA, or other electronic device with you - make no mistake - any data on those devices (especially your personally identifiable information) may be accessed by the Russian government or cyber criminals”, he said.

“Corporate and government officials are most at risk, but don’t assume you’re too insignificant to be targeted”, Evanina added. “If you can do without the device, don’t take it. If you must take one, take a different device from your usual one and remove the battery when not in use.”

The UK's spooks have issued similar warnings to those travelling to the World Cup to see the UK get knocked out in the early rounds.

Britain’s National Cyber Security Center said it was “providing expert cyber security advice to the (UK) Football Association ahead of their departure to Russia for the 2018 FIFA World Cup”.