Good to hear that the EU is taking a hard line with this nonsense. If the UK wants to turbo-charge their decline into international economic and political irrelevance by leaving the EU, let them go ahead.
I've always found this argument very amusing, given that we genuinely would be irrelevant internationally were we to become part of a United Europe.
Anyway, bring it on Merkel. It'll be fun watching you get set upon by the rabble (Podemos, SYRIZA and the like) that several of your EU partners seem likely to elect in the not too distant future.