Brčko
A significant portion of the Brčko District (48% of its area) was created from Republika Srpska's territory. Republika Srpska controlled this territory until March 8, 2000 (see the History and Mandate of the OHR North/Brcko). When the Brčko District was created, Republika Srpska's territory within the District (as well as that of the Federation of Bosnia and Herzegovina) became a shared territory of both entities. District Brčko's territory was defined as being shared by both entities as a condominium, but it was not placed under control of either of the two, and is hence under direct jurisdiction of Bosnia-Herzegovina. Republika Srpska's authorities never officially accepted the Brčko Arbitration result, but nevertheless had to comply.
Read more about this topic: Municipalities Of Republika Srpska