Can I register an overseas marriage in the UK when I return?
No, but you can have your marriage documents deposited with the General Register Office (GRO).

This isn’t compulsory, but it means your marriage certificate is kept by the GRO as an official record and you will be able to easily get copies of it in the future.

Please note: you’ll need to get your documents translated if they’re not in English.

source:

http://www.fco.gov.uk/en/travel-and-...-partnerships/