Zagreb, Croatia.

Blocking humanitarian aid in Bosnia Herzegovina should be investigated as a possible war crime, America's chief representative to the U.N. said Friday. The warning by the envoy, Madeleine K. Albright, came a day after U.N. Officials said villagers in central Bosnia were starving because a relief supplies were not reaching them.

"We put all parties on notice, that the U.S. firmly believes that preventing or hindering the delivery of humanitarian aid in this conflict should be investigated by the Prosecutor for War Crimes," Mrs Albright said at a news conference at the Zagreb airport.

She said that harassment of aid convoys fell within the jurisdiction of the newly formed U.N. War Crimes Tribunal in The Hague. Ensuring free access for relief convoys would also influence Washington's decision on whether to lift economic sanction on Serbia, Mrs. Albright said before departing fot Poland on the next leg of the European tour.

In an interview with croatian state television, she said, "we need evidence that the Bosnian Serbs are using all of their influence to guarantee free passage." She added that she favored tightening sanctions on Belgrade, but did not elaborate.