With the exception of a few agricultural goods, the CUFTA will essentially eliminate the customs duties on all imports from the Ukraine, either immediately upon implementation of the agreement, or through a tariff phase-out for passenger automobiles.
Information regarding the CUFTA can be found at https://international.gc.ca/trade-commerce/trade-agreements-accords-commerciaux/agr-acc/ukraine/index.aspx?lang=eng

The required proof of origin is a statement and is referred to in the CUFTA as the Origin Declaration.  The Origin Declaration and the various languages in which it may be completed are contained in Annex 3-B of Chapter 3 of the CUFTA.  This statement may be provided on an invoice or any other commercial document that describes the originating product in sufficient detail to enable it identification.

In order to claim Ukraine Tariff, importers must have in their possession the statement completed by the exporter in Ukraine.