Temporary expedient to close up breach (7)

I believe the answer is:

stopgap

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

'close up breach' is the wordplay.
'close' becomes 'stop' (I've seen this before).
'up breach' becomes 'gap' (synonyms. I am not sure about the 'up' bit.).
'stop'+'gap'='STOPGAP'

'to' acts as a link.

Can you help me to learn more?

(Other definitions for stopgap that I've seen before include "Temporary expedient" , "caretaker" , "A temporary substitute or solution" , "Provisional" , "Temporary measure" .)

I've seen this clue in The Telegraph.

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