Bars accepting foreign money? Certainly not (2,2,5)
I believe the answer is:
by no means
'certainly not' is the definition.
(by no means means not at all or certainly not)
'bars accepting foreign money?' is the wordplay.
'bars' becomes 'bans' (ban can mean to bar or forbid).
'accepting' means one lot of letters goes inside another.
'foreign' indicates an anagram (foreign order of the letters).
'money' is an anagram of 'ynome'.
'bans' placed around 'ynome' is 'BY NO MEANS'.
(Other definitions for by no means that I've seen before include "Definitely not" , "Forbids" , "Certainly not, perish the thought" , "Certainly not, not in any way" , "Without using any method" .)