Travel document in Kiev is accepted (4)
I believe the answer is:
visa
'travel document' is the definition.
(I've seen this before)
'in kiev is accepted' is the wordplay.
'in' says the answer is hidden in the clue.
'VISA' is hidden in the letters of 'kiev is accepted'.
(Other definitions for visa that I've seen before include "Endorsement made in a passport" , "Mark on passport" , "Travel stamp in passport" , "Travel document is required to enter Virginia" , "Addition to passport" .)