Is one surrounded by fish in this country? (7)
I believe the answer is:
tunisia
'in this country?' is the definition.
(I've seen this before)
'is one surrounded by fish' is the wordplay.
'one' becomes 'i' (Roman numeral).
'surrounded by' indicates putting letters inside.
'fish' becomes 'tuna' (tuna is a type of fish).
'is'+'i'='isi'
'isi' inserted within 'tuna' is 'TUNISIA'.
(Other definitions for tunisia that I've seen before include "African republic on the Mediterranean coast" , "African state" , "Country where Carthage is found" , "Country which contains the site of Carthage" , "Suit Ian to be in North African country" .)