Softbank is unlikely to be able to start offering mobile services after the Japanese regulator decided to split remaining frequencies between NTT DoCoMo and KDDI.

Softbank took the unusual step of complaining publicly about the decision. DoCoMo and KDDI will now share the 800Mhz frequency which the regulator says is needed to ensure smooth transfer to full 3G services. Softbank's entry to fixed-line telecoms and the broadband market, through Japan Telecom, has led to aggressive price cuts. There have been rumours the firm may reach agreement with Vodafone's struggling Japanese subsidiary.

Masayoshi Son, chief executive of Softbank, told Reuters he would not rule out taking legal action against the regulator.

A spokesman for the regulator told AFP that the 800Mhz band would not be allocated to "newcomers" until 2012. ®

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