Russian television has shown a simulation of a nuclear strike on central London with more than 850,000 deaths. The startling four minute video was aired in an apparent effort to prevent Britain from giving permission to Ukraine to allow Storm Shadow missiles to hit targets inside Russia.

A chilling simulation of what would happen if a nuclear strike hit London was aired on Russian channel Tsargrad TV.

The latest bout of nuclear sabre rattling by the Kremlin comes as the UK ponders a decision to allow Ukraine's military to use Storm Shadow missiles to strike targets deep inside Russia.