Serbia is calling for an international inquiry into its claims that rebels from Kosovo trafficked in human organs during and after its war for secession in 1998-99.
The EU mission in Kosovo is already investigating but Serbia wants the UN to oversee it.
The demand came at the annual conference of the Organisation for Security and Cooperation in Europe, meeting in Belgrade.
Serbia’s delegate Gordana Comic said: “We want justice for all those who died in such a horrible way in Kosovo, and to prevent future atrocities that could occur due to the connection between war crimes and organ trafficking.”
Last year a Council of Europe report alleged that Kosovo Liberation Army rebels killed Serb prisoners and sold their organs on the black market.
Kosovo’s current Prime Minister Hashim Thaci strongly denies claims that he led a faction which was involved.
Kosovo declared independence from Serbia in 2008, but Serbia has refused to recognise it sovereignty.