Mexican billionaire and owner of America Movil, Carlos Slim, the world’s richest man, may buy a stake in Portugal Telecom (PT) to block a possible takeover bid by Spanish operator Telefonica, reports business daily Diario Economico. The paper, citing unnamed sources, said Slim has been in contact with PT and some of its main shareholders such as Banco Espirito Santo, and has a team in Lisbon preparing the operation. According to the Financial Times today, PT’s CEO has described Telefonica’s threat of a hostile takeover as “unacceptable blackmail.”