This became clear at a Telekom general meeting on Wednesday, according to reports.
Slim agreed to receive diversified holdings worth at least 24 percent, said the CEO of the state holding company for industry OeIAG, Rudolf Kemler.
At present, Slim holds 26.8 percent of all shares of Telekom Austria. The Austrian state holding company possesses 28.4 percent.
In April, America Movil's finance head Carlos Garcia Moreno announced that his company wanted to expand in Europe. This was after Slim, who is one of the richest men in the world, signed a contract with the OeIAG about a strategic partnership of Telekom Austria.