In opinion 1 it was stated that SFRY is in process of breaking up.
Once the process in the SFRY leads to the creation of one or more independent states, the issue of frontiers must be resolved in accordance with the following principles:
All external frontiers must be respected
Boundaries between Croatia and Serbia may not be altered except by agreement freely arrived at
Former boundaries become frontiers protected by international law. Uti possidetis is today recognised as a general principle as stated by the ICJ in Burkina Faso & Mali, Frontier Dispute 1986 Its obvious purpose is to prevent the independence and stability of new states being endangered by fratricidal struggles
According to a well-established principle of IL the alteration of existing frontiers or boundaries by force is not capable of producing any legal effect.