Archer has fooled assembly with a lie (4,1,9)

I believe the answer is:

tell a falsehood

'lie' is the definition.

'archer has fooled assembly with a' is the wordplay.
'archer' becomes 'tell' (I've seen this before).
'assembly with' is an anagram indicator.
'has'+'fooled'='hasfooled'
'hasfooled' with its letters mixed up with 'a' gives 'afalsehood'.
'tell'+'afalsehood'='TELL A FALSEHOOD'

I've seen this clue in The Guardian.

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