''The cutoff of emergency food, medicine and fuel supplies could exacerbate ethnic tensions in Burundi,'' the Rome-based World Food Program said Tuesday in a statement.
Kenya on Monday cut off travel and suspended trade with Burundi in response to the recent Tutsi military coup that deposed the Hutu president. Tanzania has already sealed its borders with Burundi, effectively stopping vital fuel shipments to the landlocked country.
Five other east African countries have decided to impose sanctions against Burundi.
The World Food Program estimates it has a one-month stockpile of emergency supplies in Burundi for some 300,000 people.
''If the situation continues as is, then we'll probably have to begin seriously worrying in a matter of a couple of weeks,'' the agency said.
Ethnic fighting between Hutus and Tutsis in Burundi has killed 150,000 people since October 1993.
=A9 Copyright 1996 The Associated Press