New Delhi, April 1 -- Kushtrim Ajvazi is proud to be part of a successful business in one of the poorest countries in Europe. The company where he is a manager produces potato chips and other snacks that can be found in almost every shop in Kosovo and are exported abroad.

But Ajvazi's company faces unplanned challenges because of a steep rise in fuel prices caused by the war in Iran, whose ripple effects have reached this small corner of southeastern Europe.

The Pestova company has nearly 100 acres of potato fields in eastern Kosovo that are used to make the potato chips sold under the name Vipa. Both the firm and its distribution network were hit when the wholesale price of fuel rose from 1.10 euros ($1.27) to up to 1.7 euros ($1.96) p...