MikeMA
pfm Member
I remember Argentina being referred to as the Argentine in British and American English. According to Wikipedia its official title is the Argentine Republic - República Argentinahttps://en.wikipedia.org/wiki/Name_of_Ukraine#:~:text=Ukraine is one of a,the" on 3 December 1991.
IIUC, the convention is that "The" is a preposition for a region, not a country. Use of "the" in conjunction with "Ukraine" harks back to pre-independence and when it was a member of the Soviet Union; quite emotive when you're fighting against that happening again.
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Bob McC told me off about it once, so I dun some reading.