Mexican tycoon Carlos Slim bought a majority stake in Telekom Austria in 2014 in order to use it as a stepping stone for expansion in eastern Europe.
Telekom Austria bought the stake for an undisclosed price from current owners including Croatian companies, financial institutions and the Quaestus Private Equity Fund.
It will use cash flow to finance the deal, which is set to close in the first quarter of 2017 pending regulatory approval.