Girl wrapped in British flag (6)
I believe the answer is:
banner
'flag' is the definition.
(banner is a kind of flag)
'girl wrapped in british' is the wordplay.
'girl' becomes 'anne' (I've seen this before**).
'wrapped in' indicates putting letters inside.
'british' becomes 'br'.
'anne' placed into 'br' is 'BANNER'.
(Other definitions for banner that I've seen before include "Website advertisement" , "Standard; heading" , "Streamer for advertising" , "Ensign" , "Flag with a slogan" .)