River weeds in new ports, perhaps (3,5)

I believe the answer is:

red wines

'ports perhaps' is the definition.
(port is a type of red wine)

'river weeds in new' is the wordplay.
'river' becomes 'r' (abbreviation for river).
'new' is an anagram indicator.
'weeds'+'in'='weedsin'
'weedsin' with letters rearranged gives 'edwines'.
'r'+'edwines'='RED WINES'

(Another definition for red wines that I've seen is " Clarets, for example".)

I've seen this clue in The Guardian.

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