Brazilian specialized website Tele Sintese and newspaper O Estado de S. Paulo reported the new companies interested, citing people with knowledge of the matter.

Proposals should be delivered by Monday afternoon at the bankruptcy court in Rio de Janeiro, with a minimum price of 1.697 billion reais ($326 million), equivalent to Highline's binding proposal.

Oi and American Tower did not immediately respond to Reuters' requests for comment. IHS declined to comment.

($1 = 5.2055 reais)

(Reporting by Tatiana Bautzer; Editing by Jan Harvey)