EEC remaining active in old political system (6,6)

I believe the answer is:

ancien regime

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'old political system' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'eec remaining active' is the wordplay.
'active' indicates anagramming the letters (the letters are active/moving).
'eec'+'remaining'='eecremaining'
'eecremaining' is an anagram of 'ANCIEN REGIME'.

'in' acts as a link.

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I've seen this clue in The Telegraph.

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