Message

Value MUST be part of code list 'Country codes (ISO 3166-1:Alpha2)'.

Context
/ubl:Catalogue/cac:CatalogueLine/cac:Item/cac:OriginCountry/cbc:IdentificationCode
Test
(some $code in $clISO3166 satisfies $code = normalize-space(text()))
Code lists
Country codes (ISO 3166-1:Alpha2)
Usage
/ ubl:Catalogue / cac:CatalogueLine / cac:Item / cac:OriginCountry / cbc:IdentificationCode