Powerful relation (7)

I believe the answer is:

telling

I believe this is a double definition.

'powerful' is the first definition.
(thesaurus)

'relation' is the second definition.
(to relate a story is to tell it)

(Other definitions for telling that I've seen before include "briefing" , "Giving an order" , "Providing information" , "Counting" , "Powerful - effective" .)

I've seen this clue in The Telegraph.

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