The head of Britain's Royal Air Force has warned that we we now face an unprecedented threat in space, which could have a devastating effect on the satellites we rely on for communication, internet, bank transfers and satnav.

A defence source has told BBC defence correspondent Jonathan Beale, that Britain has already used a ground based system to jam or block the satellite communications of a hostile state.

Beale explains there is now a new arms race going on in space.

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