Has to be in Los Angeles, the 'Forbidden City' (5)
I believe the answer is:
lhasa
'forbidden city' is the definition.
(I've seen this in another clue)
'has to be in los angeles' is the wordplay.
'to be in' is an insertion indicator.
'los angeles' becomes 'LA' (abbreviation).
'has' placed into 'la' is 'LHASA'.
'the' is the link.
(Other definitions for lhasa that I've seen before include "Tibetan holy city" , "Group; stripe" , "Tibetan dog breed" , "foreign capital" , "Luxembourg's a" .)