He won't give up a German city (5)

I believe the answer is:

trier

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'a german city' is the definition.
(Trier is a city in Germany)

I don't understand the rest of the clue.

(Other definitions for trier that I've seen before include "town in Germany" , "one hears" , "One attempts" , "One making an attempt" , "Person attempting" .)

I've seen this clue in The Irish Independent.

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