You cannot have Greece, Spain and Italy out of the Euro and Portugal in. And you need to count Cyprus too.

I went by countries with political movements anti austerity, but yes that sounds reasonable.

And it would give Bulgaria and all other countries that are larger then that a free veto when the Mediterranean block is opposed.

Courtesy of the German government there is a Majority Calculator. Playing around, the only real effect of the population limit is if Germany and France and one more of UK, Italy and Spain are opposed to something. Otherwise I can't find any combination where it matters. So that one can be ignored unless Germany and France consists the nucleus of the blocking minority.

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