European Union leaders want NATO and the United States to lead efforts to keep the conflict in the Serbian province of Kosovo from spreading into an all-out war.

During a second day of security talks Tuesday among European Union defense and foreign ministers, German Defense Minister Volker Ruehe said Kosovo was a crisis the EU could not handle alone."We need the Americans," he said.

Luis Maria de Puig of Spain urged the ministers to consider intervening, but his appeal was expected to go nowhere. Many EU governments want NATO to remain the key European security provider.

The U.S.-led NATO alliance in Brussels will issue options to contain the crisis in the next two weeks. Options include sending observers to Kosovo or neighboring Albania, imposing a no-fly zone, beefing up Albania's military and police forces or staging small maneuvers of NATO and Albanian troops.

NATO Secretary-General Javier Solana said, "We have not ruled out any possibility if the situation deteriorates."

More than 150 people have died in Kosovo since March 1 in fighting between Serb and Albanian forces. Ethnic Albanians, who comprise 90 percent of the population, want independence from Serbia.

The top international mediator in Bosnia, Carlos Westendorp, said NATO peacekeepers may eventually be called on to respond to all-out fighting in Kosovo and warned of a refugee crisis.

Meanwhile, efforts to bolster the Western European Union - the EU's embryonic defense arm - remained frustrated.

"What we have is a signal from a WEU which does not know which way to turn," said Dutch Foreign Minister Hans van Mierlo, echoing criticism that EU waffling was to blame for recent Balkans unrest.