In a letter to the union dated December 11, it recommended TOT chairman and the Finance Ministry's permanent secretary to examine whether the auction would cause any financial damage to TOT.
It also suggested that if the auction would affect TOT, both should consider filing the case against the auction at the Central Administrative Court.
After Advanced Info Service's 900MHz concession granted by TOT expired in September 2015, the spectrum was returned to TOT. However, the NBTC has claimed the spectrum for reallocation. The union is of the view that the spectrum should be returned to TOT.