Lie concerned with Conservative policy (7)
I believe the answer is:
recline
'lie' is the definition.
(I've seen this before)
'concerned with conservative policy' is the wordplay.
'concerned with' becomes 're' (**).
'conservative' becomes 'c' (abbreviation commonly used in UK politics).
'policy' becomes 'line' (I've seen this before).
're'+'c'+'line'='RECLINE'
(Other definitions for recline that I've seen before include "Lie in a comfortable position" , "Lie back to rest" , "Be recumbent" , "Lie back and relax" , "Assume horizontal or leaning position as for rest" .)