Serb authorities in Bosnia have decided to challenge the country's integrity two decades after it emerged from a bloody inter-ethnic war by endorsing a decision to hold a referendum on the authority of the national court over the country's Serb-run part.

Lawmakers in the highly autonomous Serb-run Republika Srpska, which makes up post-war Bosnia together with a region shared between Muslim Bosniaks and Croats, adopted a decision Wednesday to organize the referendum in the next six months, arguing that Bosnia's national court is biased against the Serbs.

The decision was passed only a day after the international community representatives in Bosnia, including top EU and U.S. diplomats, warned Serb leaders that the proposed referendum would be "a direct threat to the sovereignty and security" of Bosnia that "cannot be tolerated."