While often mistaken for Australian, the GEICO gecko's accent is British. More precisely, southeast English (London or home counties). The British/Australian mix-up is used to comic effect in a...
According to Princeton, here are some definitions for "composition:"
the spatial property resulting from the arrangement of parts in relation to each other and to the whole; "harmonious...
It does not have either of those accents. In one of the latest commercials he says he isn't British or Australian. I was searching and i found out he has a New Zealand accent.