Group backing grasping European banker (4)
I believe the answer is:
tees
'banker' is the definition.
(I've seen this before)
'group backing grasping european' is the wordplay.
'group' becomes 'set' (both can mean a collection).
'backing' is a reversal indicator.
'grasping' indicates putting letters inside (inserted letters are held or grasped).
'european' becomes 'e' (abbreviation e.g. EU).
'set' in reverse letter order is 'tes'.
'tes' going around 'e' is 'TEES'.
(Other definitions for tees that I've seen before include "River in NE England" , "Stockton's river" , "sand-hills" , "Current" , "used by golfers" .)