Rakuten Inc. applied for a cellular frequency band with Japan's Ministry of Internal Affairs and Communications as it seeks to become the country's fourth mobile network operator, the Nikkei Asian Review reported.

The move comes less than three months after the Japanese e-commerce company announced its plan to foray into the telecommunications industry, taking on Nippon Telegraph and Telephone Corp.'s NTT Docomo, KDDI Corp. and SoftBank Group Corp.'s SoftBank Telecom Corp.

The three existing wireless carriers reportedly also applied for the 1.7GHz and 3.4GHz bandwidth that the communications ministry will free up.

Rakuten set up its mobile operator unit in January and plans to allocate $5.61 billion for infrastructure, such as cellular base stations, the Nikkei said.

Japan's communications ministry will spend about a month reviewing Rakuten's proposal, according to the report.