DTAC’s request to develop its idle 25-megahertz band on the 1,800MHz spectrum to provide a 4G cellular service, has been rejected by the National Broadcasting and Telecommunications Commission (NBTC), reports the Bangkok Post.

DTAC – Thailand’s second largest telecom – has a concession from CAT Telecom for the 1,800MHz spectrum, which the NBTC said would be violated under DTAC’s current proposal to use the spectrum for 4G services.

DTAC failed to win any spectrum in the November/December auctions, and has been relying on using the 1,800MHz spectrum to offer 4G services in what is expected to be a fiercely competitive market.

NBTC’s rejection appears to be based on the failure to prove that both DTAC and CAT have concluded an agreement over a 4G development plan, so pressure will now be mounting on DTAC to reach an accord with CAT, as noted on Mobile World Live.