TeleGeography reports that Brazilian operator Telemar (Oi) and SindiTelebrasil, an association of local telecoms companies, have submitted petitions to block a planned 3G spectrum auction, following a decision by Anatel, the country’s regulator, to bar existing operators from participating. It was said that the complainants are arguing that Anatel has failed to justify the reasons for this strategy, which is designed to permit the entrance of a new player to the market. The auction is scheduled to begin next month.