Clinton and Ashton, who are on a tour of the Balkans, want Serbia and its former province to restart EU-sponsored talks on normalizing ties, as well as resolving border issues stemming from the secession.

"It takes political will, courage even ... but we will help Kosovo and Serbia," Clinton said after she and Ashton met Prime Minister Hashim Thaci and President Atifete Jahjaga.

Prime Minister Thaci vowed that Kosovo was committed to talks with Serbia. "The dialogue is the only path that leads to the European Union ... The normalization of the relations between the two countries is in the interest of Kosovo, Serbia and the region," he said in a joint press conference with Clinton.

Kosovo, which has a 90 percent Albanian majority, declared independence in 2008. Serbia says it is willing to negotiate with Kosovo but refuses to formally recognize its sovereignty.

A major source of tension is the north of Kosovo, which has a Serb majority loyal to Belgrade. Some Serbian officials have proposed to split Kosovo along ethnic lines, but Clinton ruled this out.

"We will oppose any discussion of territorial changes or reopening Kosovo's independent status. These matters are not up for discussion," Clinton said, reiterating Washington's strong support for Kosovo's ethnic Albanian authorities.

Joining the EU

Kosovo could take a first step towards joining the EU in the first half of 2013 if it makes solid progress in the rule of law, protection of minorities and other political reforms.

Clinton told reporters that EU membership offered "the surest path to long-term stability, prosperity and peace".

Ashton said that the path to the EU will not be easy, but "in the end Kosovo will be a country where order and law are respected."

Clinton and Ashton visited Bosnia and Serbia on Monday and Tuesday and were scheduled to fly to Albania. Clinton will end her Balkan tour in Croatia.

hc/slk (dpa, AP, AFP)