MEXICO CITY - Latin American wireless carrier NII Holdings Inc plans to bid for new frequencies to bolster its coverage in Mexico as it deploys 3G technology across the region to improve services and boost client base.

We are interested in the national coverage, Gustavo Cantu, vice president of NII's Mexico operations, told Reuters on Wednesday.

NII operates in Mexico, Brazil, Argentina, Peru and Chile under the Nextel brand.

The Mexican government this month launched the long-awaited terms for mobile-phone frequency auctions, and hopes to unveil winners by mid-year. Such a big sale of added wireless capacity in the country is the first in at least a decade.

Cantu said Nextel Mexico was exploring how to approach the auction, which will give companies the right to operate blocks of frequency in the 1.7 Ghz and 1.9 Ghz bands.

Other rivals are willing to team up to improve their chances of buying the best bands. The process is expected to lure blue chips like Spain's Telefonica and Mexican media company Televisa.

Local newspaper Excelsior said in a column this week that Televisa  was ready to pay $1 billion for a stake of between 20 percent and 30 percent in Nextel Mexico.

Asked about the chance of NII siding with the world's biggest producer of Spanish-language media content, Cantu said, Those are only market rumors. But he did not deny the report. Televisa was not available for comment.

Cantu said NII is busy deploying 3G services in Latin America, which would allow the company to catch up with regional leaders America Movil, controlled by Mexican tycoon Carlos Slim, and Telefonica. (Reporting by Cyntia Barrera Diaz; editing by John Wallace)