Sanction unproductive without fine (5)

I believe the answer is:

allow

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'sanction' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for allow that I've seen before include "Give permission to" , "Sanction" , "Permit or agree" , "Permit, consent to" , "Licence" .)

I've seen this clue in The Times.

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