Senior politician getting taxi in film with member of the clergy (7,8)
I believe the answer is:
'senior politician' is the definition.
(I've seen this before)
'taxi in film with member of the clergy' is the wordplay.
'taxi' becomes 'cab' (synonyms).
'film' becomes 'et' (E.T. the Extra-Terrestrial).
'with' says to put letters next to each other.
'member of the clergy' becomes 'minister' (a church minister).
'getting' is the link.
(Other definitions for cabinet minister that I've seen before include "May perhaps" , "member of government" , "went down to provide 22 24 [WHISKY GALORE] - with 17d" , "senior politician" , "high-ranking member?" .)