Telekom Austria, the central and eastern European unit of Mexican tycoon Carlos Slim's America Movil, operates in seven eastern European countries, most of them in the former Yugoslavia.
While Telekom has said before that it intends to expand internationally, the comments are the company's most specific on those plans in months.
"If you don't expand you will not be relevant," Plater told an economic reporters' club in Vienna, outlining a range of priorities.
One priority "is to go to new countries, that's a tactical move ... We will keep on looking east," he said, without elaborating on specific countries. "We can do acquisitions for a billion" euros, without raising additional equity.
Plater said the company planned to "consolidate" in Croatia, Belarus and Macedonia.