The two companies will jointly forward the roaming deal, which was agreed late last month, to the National Broadcasting and Telecommuni-cations Commission (NBTC) for acknowledgement.

The roaming fee is reportedly 35-40 satang per minute. A telecom analyst estimated that the agreement with DTAC would cost AIS around Bt2 billion if the roaming lasted for six months and Bt4 billion if for one year.

Second-generation mobile phones compatible with the 900-megahertz spectrum usually can function on 1,800MHz as well.

An AIS source said it had so far migrated 1.6 million of its 12 million 2G subscribers on the 900MHz network to the 3G and 4G systems of its subsidiary Advanced Wireless Network (AWN).

AIS earlier operated its cellular service on 900MHz. After its concession ended last September, the watchdog reclaimed the spectrum for auction. True Corp and Jasmine International each won a 900MHz licence at an NBTC auction last December. They have to pay the first instalment of the licence upfront fee by March 21.

Once either True or JAS pays the first instalment, the NBTC will grant the licence to it, which means AIS will have to switch off its 900MHz service. This has forced AIS to offer heavy promotional campaigns to woo its 2G subscribers to the AWN network. It budgeted around Bt8 billion to offer subsidised handsets to encourage customers to move to AWN.

This week, True launched a campaign to woo this customer group to its network.

In a related matter, AIS yesterday denied an allegation by True Corp that AIS was blocking calls by its 2G subscribers to True’s cellular-service call centre.

Wilai Keangpradoo, AIS senior vice president for public relations, said the company was using all communication channels to inform its 2G customers about the privileges they will gain from switching to AWN’s 3G or 4G service. Therefore, when the 2G customers call out, they will hear this information first before their calls are routed to the dialled numbers. They will hear such messages for only one day.

The customers can cancel this information message by dialling *247*1# free of charge, and this is also told to them.

True Move H Universal Communication Company yesterday asked the Consumer Protection Police Division to investigate what it claimed were nationwide complaints of mobile customers being blocked from contacting TrueMove H Care 1331 to access information on switching from AIS to TrueMove H while keeping their existing phone numbers.

TrueMove H also said the beneficiaries and parties responsible for such actions could be AIS and its subsidiaries. If so, it took the view that such a practice breached the Computer Crime Act and the Telecommunication Business Act.

True claimed that when customers used the AIS network to call TrueMove Care 1331, their calls were immediately terminated, or re-routed to AIS’ interactive voice response promoting its services, and then the call was terminated.

True recently asked the NBTC to investigate the complaints.