Press association, modern and wise about entering US city (4,6)

I believe the answer is:

news agency

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'press association' is the definition.
'news agency' can be an answer for 'press' (thesaurus). I am not certain of the 'association' bit.

'modern and wise about entering us city' is the wordplay.
'modern' becomes 'new' (synonyms).
'and' is a charade indicator (letters next to each other).
'wise' becomes 'sage' (similar in meaning).
'about entering us city' becomes 'ncy' (I can't explain this - if you can you should believe this answer much more).
'new'+'sage'+'ncy'='NEWS AGENCY'

Can you help me to learn more?

(Other definitions for news agency that I've seen before include "E.g. Reuters" , "information source" .)

I've seen this clue in The Telegraph.

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