Nevertheless, a definition of features of a nation that has the right to self-determination, is not universally accepted. It is rather a reference point that is used by UNESCO. Nevertheless, they are the most common features. Thus, people that wants to exercise its right to self-determination is likely to have to prove its right. In addition, recognition by the world community of a nation is rather a political decision than has a legal status.
As I can see, for the people in the southern region it is possible to exercise their right when they choose their political status, the scope of their participation in the political sphere and the form of their government within State A.
It should be noted, during the discussion of the draft of the Vienna Convention, proposals aimed at the facilitation of the withdrawal procedure were declared. However, we do not need to exaggerate a problem which arises from the requirement of a State`s withdrawal to be in written. Nevertheless, it would be inconsistent if a reservation, which undoubtedly must be in writing, could be withdrawn simply through an oral statement; this may lead to a considerable uncertainty for the other Contracting Parties that will receive a written text of the reservation, but were not previously aware of a withdrawal of any other State.
Even if we assume that the public announcement of withdrawal is sufficient, we must determine whether a statement of the Head of State or the Foreign Ministry can create legal consequences. In contemporary international law, a State may be legally bound, even when it had acted unilaterally within their representatives.