Deplore Lithuania's housing? So be it! (6)
I believe the answer is:
lament
'deplore' is the definition.
(I know that deplore can be written as lament)
'lithuania's housing? so be it' is the wordplay.
'lithuania' becomes 'LT' (internet domain code for Lithuania).
'housing?' is an insertion indicator.
'so be it' becomes 'amen' (I've seen this in another clue).
'lt' placed around 'amen' is 'LAMENT'.
(Other definitions for lament that I've seen before include "Song of sorrow" , "Express grief" , "Dart-throwing line" , "Expr. of grief; mourn" , "Mourn (a person's death)" .)