The Serbs, the Bosniaks and the Croats have all agreed to change the constitution so Bosnia can apply for European Union membership, but the Serbs only want to do that if U.S. and EU negotiators leave the talks. The Bosniaks and Croats want them to stay.

Last week, senior U.S and EU officials gave Bosnian leaders a proposal on how to change the constitution.

Milorad Dodik, the prime minister of the Bosnian Serb region, rejected the draft, and he scheduled another round of talks on Friday that would exclude the foreign mediators. But only he and officials from three small parties showed up.

Bosnia's constitution divides the country into a Serb Republic and a Bosniak-Croat Federation, linked by a common parliament, a three-member presidency and a council of ministers. The division of authority remains unclear, and each side interprets it in different ways.

An international administrator acts as a referee and has the power to fire local officials and impose laws.

In attempts to reform the constitution, Bosnian Serbs seek more autonomy for their mini-state, and Bosniaks and Croats want to abolish the country's' division. The proposals put forward by the EU and U.S. would strengthen the power of the state.