Write to the UK Government...  
  The following links are to Pro Forma ( prepared ) letters that you can copy and paste and feel free to edit to add to or amend as you see fit.   The more people who do this, the better.

To the Secretary of the Home Office, Rt Hon Priti Patel
    the Minister of Justice
    Belmarsh Prison
  All MPs in the British Labour Party,

 The British Conservative Party,

 The British Liberal Democratic Party 

, The Scottish National Party

 and to all other British MPs.