Politician needs way to reverse domestic problem (3,3)
I believe the answer is:
dry rot
'domestic problem' is the definition.
(fungal problem in a house)
'politician needs way to reverse' is the wordplay.
'politician' becomes 'tory' (term for a Conservative Party politician).
'needs' is a charade indicator (letters next to each other).
'way' becomes 'rd' (short for road).
'to reverse' says the letters should be written in reverse.
'tory'+'rd'='toryrd'
'toryrd' backwards is 'DRY-ROT'.
(Other definitions for dry rot that I've seen before include "housing problem?" , "Timber disease" , "Decay of unventilated wood" , "Fungus causing timber decay" , "corruption" .)