The European Union reminded the tripartite government in Bosnia-Herzegovina on Today that any division would harm its chance to join the group, according to dpa. The EU representative at UN headquarters in New York said progress has been made to strengthen a Bosnian government composed of Bosnian Serb, Croat and Moslem leaders, but major challenges remain. "Nationalist, anti-Dayton rhetoric challenging the sovereignty, territorial integrity and constitutional order of Bosnia-Herzegovina is undermining efforts of its political leaders to find common language and compromise," said the Czech Republic's UN Ambassador Martin Palous. Palous said during a Security Council debate on the situation in Bosnia that the tripartite government has made "inadequate" reforms required to gain accession to the EU. Bosnia is also trying to join NATO. "The EU membership of Bosnia-Herzegovina, as a single and integral state, remains an ultimate goal, which will serve the stability, reconciliation and the future not only of this country, but also the whole region of the Western Balkans," Palous said. US Vice President Joseph Biden warned Bosnia-Herzegovina during a recent visit to the Balkans to avert political fragmentation. Bosnia- Herzegovina ended a destructive three-year ethnic conflict in 1995 with the Dayton peace agreement. In Sarajevo on Wednesday , the prime minister of Muslim-Croat Federation of Bosnia-Herzegovina, Nedzad Brankovic, resigned amid tensions with other members in the country's tripartite leadership. Brankovic submitted his resignation letter to the Bosnian presidency, a day after Sulejman Tihic, a member of a tripartite presidency, was re-elected as the head of largest Muslim Party of Democratic Action (SDA). Tihic, whose party had nominated Brankovic as premier after winning the elections in 2006, is now demanding his resignation after a Sarajevo court indicted him for the abuse of power.