(Adds information on bidders, deadline for offers)
By Gram Slattery and Tatiana Bautzer
SAO PAULO, Aug 7 (Reuters) - Mobile carrier NII Holdings Inc is expecting to receive offers for its Nextel unit in Brazil in September, one person with knowledge of the matter said on Tuesday, as a long-awaited consolidation in Brazilian telecoms shows signs of kicking off.
The source, who asked for anonymity since discussions are private, said Telefonica Brasil SA is among the interested parties in Nextel Brazil, alongside Telecom Italia SpA unit Tim Participações SA and America Movil SAB de CV subsidiary Claro.
Access Industries, which holds a 30 percent minority stake in Nextel, is also interested in increasing its stake in the company.
Representatives for TIM Participacoes, NII, and Claro did not immediately respond to requests for comment on Tuesday. Representatives for Telefonica Brasil have previously declined to comment, while Access Industries has not responded to comment requests.
NII Chief Financial Officer Daniel Freiman confirmed during an earnings call with analysts on Tuesday a Reuters report on the unit sale, adding Rothschild & Co was advising on the process.
A Nextel sale would give players in Brazil's crowded telecom sector a long-awaited, but rare chance at consolidation. While Brazilian telecom Oi SA has been floated as an acquisition target, any sale of that firm has been slow in coming.
Roberto Rittes, head of Nextel Brazil, said on the conference call that industry regulator Anatel was likely to raise spectrum cap limits in the fourth quarter, which would speed up a sale, adding he saw no serious opposition to the process.
NII shares soared as much as 31 percent on June 28 after Reuters reported NII had hired Rothschild to explore a sale of Nextel. The stock has risen some 1,400 percent year-to-date amid bets of a takeover.
Freiman declined to comment during the call on potential bidders, saying only that "strategic discussions" were ongoing.
A sale to local rivals will depend on Anatel increasing spectrum caps. Much of Nextel's value comes from its spectrum rights in the wealthier states of Sao Paulo and Rio de Janeiro, but companies like TIM and Telefonica Brasil are already running up against current limits in those states.
Nextel Brazil has about 3 million customers, but its earnings before interest, taxes, depreciation, and amortization (EBITDA) are close to zero.
Nextel Brazil is NII's division operating in Latin America after it exited operations in Peru, Chile and Mexico, where its unit fetched $1.9 billion from AT&T Inc three years ago. (Reporting by Gram Slattery Editing by Paul Simao and Chris Reese)