Russian’s ready to import British debris (6)
I believe the answer is:
rubble
'debris' is the definition.
(synonyms)
'russian's ready to import british' is the wordplay.
'russian's ready' becomes 'ruble' (I can't explain this - if you can you should give a lot more credence to this answer).
'to import' indicates putting letters inside.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'ruble' enclosing 'b' is 'RUBBLE'.
Can you help me to learn more?
(Other definitions for rubble that I've seen before include "Mass of rough fragments of brick or stone" , "Bits of demolished building" , "Demolition site debris" , "Bits of broken stone, brick etc" , "Debris, detritus" .)