(Telecompaper) The CEO and chairman of Portugal Telecom, Henrique Granadeiro, has resigned. The move comes three weeks after the Portuguese operator was forced to reduce its stake in the merger with Brazil's Oi due to a controversial debt position of EUR 900 million in an associated company of one of its major shareholders. Portugal Telecom also said its board of directors and executive committee had never approved any investment in that debt. The company has contracted PWC to audit all investment in the Espirito Santo Group debt made by Portugal Telecom.