Leaders of Bosnia's three main ethnic groups, meeting in Washington, have agreed to reform their divided government. The Bosnian Serbs also committed to apprehending indicted Balkans war crimes figures still at large. 

The reform agreement and pledge on the war crimes fugitives added major substance to what otherwise would have been a ceremonial event here marking the 10th anniversary of the Dayton peace accords for Bosnia.

Making the announcement after meetings with top U.S. diplomats, the Bosnian Croat, Muslim and Serb leaders committed to constitutional changes by next March that would streamline the government in Sarajevo including the presidency, now a cumbersome three-way rotation.

Also, in the face of U.S. and European pressure, the Bosnian Serbs called for the immediate surrender of the two leading Balkans war crimes figures still at large, wartime Bosnian Serb President Radovan Karadzic and his military chief, Ratko Mladic.

Both have been charged by the Balkans war crimes tribunal at the Hague with crimes against humanity, notably the killing of some eight thousand Bosnian Muslim men and boys at Srebrenica in 1995.

The statement said the two fugitives do not represent the interests of the Bosnian Serb entity, the Republika Srpska, or of Bosnia-Herzegovina as a whole. It said if they do not give themselves up, the Serb entity will undertake all possible measures to find and apprehend them.

At a luncheon meeting with Bosnian political leaders, Secretary of State Condoleezza Rice said the promised constitutional changes are a historic step forward, and essential if Bosnia is to reach the goal of full integration into the Euro-Atlantic community.

But she made clear that goal cannot be reached as long as the two wartime Bosnian Serb leaders are still at large:

"Bosnia and Herzegovina must fully confront the demons of its past, in particular the urgent and long-overdue need to bring to justice war criminals like Ratko Mladic and Radovan Karadzic. We will never forget the massacre at Srebrenica. And America's position is clear and uncompromising. Every Balkan country must arrest its indicted war criminals or it will have no future in NATO," Ms. Rice said.

Ms. Rice said the words of the Bosnian Serb statement are encouraging but they must now lead to serious action.

U.S. officials believe the war crimes figures have been given refuge at times in both the Republika Srpska and in Serbia itself.

A senior U.S. diplomat said the statement should end  the hero status enjoyed by the two among some Serb hard-liners, and put pressure on those sheltering them to turn them over to authorities.

The current chairman of the Bosnian presidency, Ivo Miro Jovic, also addressed the luncheon gathering, stressing gratitude for the U.S.-led military commitment that restored peace to Bosnia, and subsequent international aid.

Heard through an interpreter, Mr. Jovic said the way is now open to a brighter future for his country:

"This key that opens this door to the future has been given to us, but only if we know how to use it and open the door. This key is still being brought to the lock with the help of our friends here in the United States and Europe, and I'm deeply convinced that the future of Bosnia-Herzegovina is guaranteed, and in front of Bosnia-Herzegovina, there are brighter and better days."

Secretary Rice also stressed the need for an early resolution of the lingering ethnic dispute in neighboring Kosovo, saying the United States fully supports U.N.-led talks on the region's political future that began this week.

Still legally part of Serbia, Kosovo has been administered by the United Nations since 1999, when a NATO air campaign ended a Serb military crackdown on ethnic-Albanian separatists.

Ms. Rice said vision, courage and compromise are needed for an agreement enabling all Kosovars to live freely and in peace.