This month old NI police need time to train (8)
I believe the answer is:
instruct
'train' is the definition.
(thesaurus)
'this month old ni police need time' is the wordplay.
'this month' becomes 'inst' (letter-writing abbreviation for this month).
'old ni police' becomes 'ruc' (Royal Ulster Constabulary, Northern Irish police).
'need' is a charade indicator (letters next to each other).
'time' becomes 't' (abbreviation).
'inst'+'ruc'+'t'='INSTRUCT'
'to' acts as a link.
(Other definitions for instruct that I've seen before include "Direct; teach" , "Command; teach" , "Teach or give orders to" , "Coach" , "Give lesson or order to" .)