The NTC will charge cellular operators only Bt1 per number per month for the more than 30 million existing mobile-phone numbers, and the same rate for numbers issued by new operators in future.

Cellular operators will also have to pay the NTC Bt120 per year for every number they fail to sell within a year and 120 days of being allotted the number, the source said.

The annual fee for special three-digit phone numbers will be Bt12 million per number and Bt1.2 million for four-digit numbers.

The charges will take effect next month when the NTC officially introduces the numbering plan, which will increase the phone numbers in Thailand from the current 90 million to 300 million in order to solve the shortage.

The NTC will hold a press conference on the plan tomorrow.

The plan will have all mobile-phone numbers begin with 08, followed by eight digits. For example, a number currently starting with 01 will start with 081. The numbers of fixed-line telephones will not change.

Cellular operators have already prepared the technology to adopt the new numbering plan.

In a related matter, the NTC is expected to introduce regulations governing phone numbers used by the media for SMS voting by their audience three months after the new numbering plan is introduced. It will also assign new numbers for televoting, but has yet to decide the fee it will charge TV, radio and other media operators.

The NTC considers the current arrangements for televoting to be too disorganised.

 "It's time to impose regulations on the phone numbers for SMS voting and also on phone numbers to download content because there is no order at all," said NTC commissioner Sudharma Yoonaidharma.

Usanee Mongkolporn, The Nation