Thai Prime Minister Prayuth Chan-ocha said in an executive order last week that telecoms operators should be given more time to make payments because intense competition was hampering their ability to pay for 900-MHz licences.

However, the National Broadcasting and Telecommunication Commission (NBTC) said it would only allow the payment period to be extended if operators participate in an auction for 700 MHz licences in June.

"If operators do not accept the condition to enter the bidding for 700 MHz then they will not be able to get the extension for 900 MHz," Takorn Tantasith, NBTC Secretary-General said, adding operators must apply for the extension by May 10.

NBTC said the new payment plan would be 10 installments over 10 years, compared with an original four installments over five years.

That would mean operators such as Advanced Info Service PCL (AIS) and True Corp, which won their licences in 2016 for about $2 billion each and were supposed to pay the final installment next year, could now pay the remaining amount over six installments from next year to 2025.

Meanwhile, Total Access Communication Pcl, which won a spectrum licence for $1.2 billion in November, could now pay in eight more installments from next year to 2027, instead of the old deadline of 2022.

Representatives of all three companies, who met with NBTC on Wednesday, were non-committal on the requirement to bid for new spectrum.

Weerawat Kiattipongthaworn, chief corporate officer of AIS, said the company would apply for the payment extension but that its board would have to discuss the conditions of 700 MHz bidding before committing to the new arrangement. He added that NBTC had given operators too little time to decide.

Rajiv Bawa, head of corporate affairs at Total Access, said the company would seek further talks with NBTC before deciding its next move.

Adhiruth Thothaveesansuk, vice chairman of the executive committee of True Corp, welcomed the payment extension, but also said the company would have to discuss the requirement to bid for new spectrum before deciding.

"The telecom industry here has not reached the break even point and growth has been slowing down," he said.

(Reporting by Panarat Thepgumpanat and Panu Wongcha-um; Editing by Mark Potter)