Share of permit curtailed action abroad (10)
I believe the answer is:
allocation
'share' is the definition.
(I've seen this before)
'permit curtailed action abroad' is the wordplay.
'permit' becomes 'allow' ('allow' can be a synonym of 'permit').
'curtailed' means to remove the last letter.
'action abroad' becomes 'cation' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'allow' with its last letter taken off is 'allo'.
'allo'+'cation'='ALLOCATION'
'of' is the link.
(Other definitions for allocation that I've seen before include "Allotment" , "budget" , "Distribution, assignment" , "Share" , "Apportionment" .)