Firm agreement (7)

I believe the answer is:

compact

I believe this clue is a double definition.

'firm' is the first definition.
(similar in meaning)

'agreement' is the second definition.
(compact can mean an agreement)

(Other definitions for compact that I've seen before include "Tightly-knit, agreement" , "An official agreement" , "Neatly packed" , "Condense" , "Dense; agreement" .)

I've seen this clue in The Globe and Mail, The Guardian and The Telegraph.

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