The Speaker’s skill? Alternatively some MP? (7)
I believe the answer is:
oratory
'the speaker's skill?' is the definition.
'alternatively some mp?' is the wordplay.
'alternatively' becomes 'or'.
'some' becomes 'a'.
'mp?' becomes 'tory' (Tory is a type of Member of Parliament).
'or'+'a'+'tory'='ORATORY'
(Other definitions for oratory that I've seen before include "Art of public speaking or small chapel" , "Small chapel for private worship" , "Gift of the gab" , "School" , "Private chapel; art of public speaking" .)