Britain would be dangerously exposed to a devastating Russian cyber attack if digital TV signals are switched off and the UK is left reliant on the internet, national security experts have warned.

The National Preparedness Commission (NPC) said the Government could find itself unable to communicate emergency messages to millions of households if plans to turn off the Digital Terrestrial Television (DTT) network as soon as 2034 are pursued.

Arqiva, which transmits digital TV and radio signals from 1,450 UK mast sites, agreed that relying on the internet alone to ensure broadcast transmission and spread vital messages to reassure the population in the event of a crisis was a huge risk.

Shorts

Until now, resistance to switching off DTT (or Freeview) has centred on the cost of moving to online-only TV for lower-income groups. But the latest warnings suggest a premature switch-off should be considered a national security risk.