Thailand's telecommunications regulator Friday filed an appeal to the Supreme Administrative Court, seeking to overturn an injunction against its planned auction of third-generation mobile licenses.

The move comes after the Central Administrative Court late Thursday issued an injunction against the auction, scheduled to kick off on Monday, after state-owned CAT Telecom alleged the National Telecommunications Commission has no authority to grant the 2.1 gigahertz frequency spectrum to successful bidders. It also argued that parts of the regulations related to the licensing will create "unfair" competition and cause state agencies to lose revenue.

The spectrum is being sold to facilitate the launch of 3G technology in the country. State-owned operators have challenged the legitimacy of the NTC to oversee industry issues related to the technology pending the commissioning of a new regulator.

The long-delayed 3G service license auction has made Thailand among the last countries in Southeast Asia to fully deploy advanced wireless technology. The process has repeatedly been delayed due mainly to the absence of an independent body to regulate broadcasting frequencies, as well as changes in state administrations.