The top international representative in Bosnia, Carlos Westendorp, has said Bosnian Serbs risk losing international aid if they continue their boycott of the country's federal presidency.
The Serbs took part in a presidency meeting on Tuesday after being ordered to do so by Mr Westendorp.
But they say the boycott can only be ended by a decision of the parliament of the Serb Republic, which together with the Muslim-Croat Federation makes up Bosnia.
The Serb representatives began the boycott after an international tribunal made the disputed town of Brco a neutral district, instead of handing it over to the Serbs.
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