Use thread to mend frame (6,2)

I believe the answer is:

stitch up

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

I cannot understand how the rest of the clue works.

(Other definitions for stitch up that I've seen before include "Mend" , "Fix (situation) to someone's advantage (colloq.)" , "Incriminate by unfair means" , "frame" , "Falsely incriminate" .)

I've seen this clue in The Telegraph.

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