What’s the origin of unagreed?
I can find the word in Collin's Dictionary, used in parliamentary publications, as well as in American news articles.
However it's lacking from Merriam-Webster and there's no detail about it on Wiktionary.
Is this a Britishism that has started leaking across to American publications? Or was it originally American but has fallen out of use?
The etymology is obvious, but I'm looking for where the word originated.
Mainly due to its current meaning of 'not agreed' as opposed to the expected meaning if un-agreed (to undo an agreement).