US Secretary of State Hillary Clinton on Tuesday urged war-scarred Bosnia to join the EU and NATO to ensure stability as she told Bosnian Serb leaders to drop separatist threats. \"We believe that joining the European Union and NATO offers this country the best path to lasting stability and prosperity,\" Clinton said after meeting Bosnia\'s three presidents at the start of her five-nation Balkans tour. She also lashed out at Bosnian Serb leaders who have repeatedly threatened to break away from the country, saying Bosnia\'s territorial integrity was not debatable. \"It is totally unacceptable that 17 years after the war ended, some still question Bosnia and Herzegovina\'s sovereignty and territorial integrity,\" she said at a joint press briefing in Sarajevo with EU foreign policy chief Catherine Ashton. \"The Dayton Accords must be respected and preserved -- period,\" she added. The US-brokered peace deal which ended the 1992-95 war between Bosnia\'s Muslims, Serbs and Croats divides the country into two semi-autonomous entities -- the Serbs\' Republika Srpska and the Muslim-Croat Federation. The statelets each have their own government and are linked only by a weak central administration. Seventeen years after the end of the devastating 1992-95 war, Bosnia is more divided than ever. The Serbs have fiercely opposed calls for central institutions to be strengthened and have repeatedly warned that their entity could break away and negotiate EU entry separately. Sarajevo lags behind its neighbours in their progress towards joining the EU as it is the only Balkans country that has yet to apply for EU membership. \"I urge all of Bosnia and Herzegovina\'s leaders to find common ground and act in the interests of the people... Key reforms have not yet been made,\" Clinton said. \"There is no doubt among 27 EMU members that your future is in EU,\" EU foreign policy chief Ashton said. After Bosnia, Clinton and Ashton travelled to Belgrade where they are due to meet President Tomislav Nikolic and Prime Minister Ivica Dacic to press Serbia to restart the EU-brokered dialogue with Kosovo. Serbia rejects Kosovo\'s unilateral 2008 proclamation of independence, which is recognised by some 90 states including 22 of the EU\'s 27 members and the United States. Talks between Belgrade and Pristina, launched in March 2011 under EU auspices, were suspended before May polls in Serbia, won by nationalists. However, Dacic met his Kosovo counterpart Hashim Thaci two weeks ago in Brussels, signaling a new phase. Serbia is an EU candidate, and Kosovo hopes to formalise ties, but the bloc has made clear to both that they must restart talks and show concrete results. Serbian analysts said the visit at this time was a way to step up pressure on Belgrade and Pristina to implement agreements already concluded in the talks earlier on freedom of movement and border management. Clinton last visited Bosnia, as well as Serbia and Kosovo -- which emerged out of the 1990s collapse of the former Yugoslavia -- in 2010. After her stop in Belgrade Clinton travels on to Pristina where she will meet Kosovo Albanian leaders Wednesday during the day. The secretary of state will end her tour in Croatia and Albania, which joined the NATO transatlantic military alliance in 2009. Of the six ex-Yugoslav nations, only Slovenia has so far joined the European Union in 2004, while Croatia is due to become a member in July.