The base has a standard polished pontil mark and a fair amount of wear; a picture will add nothing. The top of the handle has been flattened using something that wasn't smooth.
I don't think it Polish; it is everso slightly more "handmade" and more "designer" than my two known Krosno pieces. The Poles are not the only people to make large jugs.
Sue, I noted the similarity with the early Caithness too