As Fellini said to directors, 'Quickly, get on!' (3,6)

I believe the answer is:

all aboard

'quickly get on' is the definition.
(eg phrase before a train departs)

'as fellini said to directors' is the wordplay.
'as fellini said to' becomes 'alla' ('to' in Italian - Federico Fellini was Italian).
'directors' becomes 'board' (board of directors).
'alla'+'board'='ALL ABOARD'

I've seen this clue in The Guardian.

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