Would an independent Scotland, Catalonia or Flanders automatically be part of the European Union? There is no simple solution provided for this eventuality in the 1978 Vienna Convention, nor in prior international conventions, nor though strict application of European law, according to which each state would come under the standard accession procedure, and therefore would be subject to veto by other member states. The singular nature of the European Union and simple common sense cali for a solution that is negotiated at every stage.