It's less the UK in itself, more Scotland. They were fine with EU's head speaking to be fair, the SNP may disagree with him but the man carefully worded it and other countries have kept quietly to themselves.
Where the issue is at the moment is if the English/England/London/Westminster government speak, that seems to cause problems. Scotland discussing leaving the union, does the rest of the UK have a right to say? A right to say "sorry, we won't accept that proposal if you do leave" or set out their own terms? Or should the rest of the UK keep quiet, no matter how it affects the rest of us? Should Cameron/Miliband/Osborne/Balls speak or forever hold their peace?
“You, are a rebellious son who abandoned his father. You are a cruel brigand who murdered his lord. How can Heaven and Earth put up with you for long? And unless you die soon, how can you face the sight of men?”