Area of Russia, not Southern European region (6)
I believe the answer is:
iberia
'european region' is the definition.
(I've seen this before)
'area of russia not southern' is the wordplay.
'area of russia' becomes 'Siberia' (Siberia is a Russian region).
'not' indicates named letters should be taken away.
'southern' becomes 's' (abbreviation).
'siberia' with 's' taken out is 'IBERIA'.
(Other definitions for iberia that I've seen before include "W. European peninsula" , "Old name for Spanish peninsula" , "Spain and Portugal together" , "Peninsula that was Roman province" , "Peninsula encompasing Spain and Protugal" .)