Mobile phone giant America Movil (>> America Movil SAB de CV), the jewel of Slim's empire, said on Monday it made four separate transactions to buy an aggregate 6 million ordinary shares of KPN (>> KPN KON), bringing its holding in the Dutch firm to 7.3 percent.

"All these transactions were entered into a price in cash of 7.8 euros per ordinary share," the company said in a statement. KPN shares closed at 7.769 euros on Monday.

This is America Movil's second such purchase in less than two weeks. On May 31, the company boosted its KPN holding to 5.01 percent although it did not mention the price then.

America Movil's move comes after news that KPN will kick start the sale of its Belgian BASE mobile phone business to fend off Slim's bid for the whole group.

KPN "felt threatened by the America Movil bid," said analyst Valeria Romo at brokerage Monex. "They are somehow dismantling the business by selling units and that is perhaps giving KPN shareholders some uncertainty."

Slim launched an offer last month for up to 27.7 percent of KPN. The offer, which pays 8 euros per share tendered, is valid through June 27, but could be extended.

"The terms for the KPN offer, including the price, have not changed," said a spokeswoman for America Movil after the company revealed its bigger stake in KPN.

Slim was at a United Nations event in Geneva on Monday, where he talked about his family, social programs and even gave tips to a 15-year-old on what to do with his life. He declined comment to Reuters on his European expansion plans.

With little room left to grow in Latin America, the world's richest man has now set his eyes on new territories, making the Netherlands and Austria the stepping stones.

Slim, 72, a savvy investor with a keen eye for troubled companies, put KPN in a difficult situation by giving the company only a few weeks to convince shareholders to reject an offer it believes is too low.

The Mexican businessman plans to spend around $3.25 billion in his first foray into the Netherlands, where KPN's performance has struggled over the past year.

Last week, a top America Movil executive told Reuters that the Mexican company had built up a 4.1 percent stake in Telekom Austria (>> Telekom Austria).

America Movil shares ended up 0.49 percent at 16.54 pesos on Monday.

(Additional reporting by Tom Miles and Tomas Sarmiento; Editing by Andre Grenon and Ryan Woo)

By Cyntia Barrera

Stocks treated in this article : America Movil SAB de CV, KPN KON, Telekom Austria