UN Kosovo mission chief Farid Zarif spoke to the UN Security Council on November 29 -- one day after clashes between ethnic Serbs and NATO-led peacekeepers left 30 NATO soldiers and some 100 Serbs injured.
The violence occurred as NATO sought to remove roadblocks set up by the Serbs.
The UN envoy described the northern part of Kosovo, where Serbs reject rule by Kosovo's majority ethnic Albanians, as "extremely volatile."
He said the "combined factors of frustration, fear, and mistrust could easily and quickly provide the spark that could ignite violence."
The envoy said the heightened tensions were partly caused by the politics of elections in Serbia due next spring, as well as what he called the "current political dynamics" of the ethnic Albanian-dominated Kosovo government.
The envoy called for "strong, united leadership from the international community" to try to reduce ethnic tensions in Kosovo.
with agency reports