Statutory declaration of COMMON-LAW union

[rado]

Is the Statutory declaration of COMMON-LAW union required when we both, me and my common-law partner, are non-canadian citizens applying from outside of Canada? Applying under skilled immigration.

If yes, do I need to send it with the full documents to the specific visa office (Singapore) along with other proof of common-law realtionship, such as joint bank statements, joint lease, Household purchases, etc.?
Or wait for the VO to ask for the proof of common-law union?

Thanks a million, million times for your opinion.