Alarm about European request (6)
I believe the answer is:
appeal
'request' is the definition.
(appealing is a kind of requesting)
'alarm about european' is the wordplay.
'alarm' becomes 'appal' ('appal' can be a synonym of 'alarm').
'about' is an insertion indicator.
'european' becomes 'e' (abbreviation e.g. EU).
'appal' enclosing 'e' is 'APPEAL'.
(Other definitions for appeal that I've seen before include "Request for charity donations" , "Charm; entreaty" , "Legal procedure" , "A crustacean" , "Request made to umpire" .)