Bangladesh's largest mobile-phone operator by subscription has been cleared to use the new series on some conditions, BTRC Chairman Shahjahan Mahmood told bdnews24.com on Sunday.
"The decision was made at a meeting of the commission today. A new number series has been given to Grameenphone on some conditions," he said.
The BTRC chief, however, did not reveal the conditions.
Grameenphone applied for the new prefix last year, saying around 100 million numbers with '017' prefix would soon be exhausted.
The BTRC chief said Grameenphone was given the series because they presented arguments.
"Moreover, if we receive a new prefix we will still need some time to incorporate it into our system before we can put it to use," he added.
According to BTRC, Grameenphone had around 57 million customers in June. The total of mobile-phone subscribers was around 131.4 million at the time.
In line with National Numbering Plan, mobile-phone numbers start with '01'.
Grameenphone is using '017' as the prefix, Citycell '011', Teletalk '015', Airtel '016', Robi '018' and Banglalink '019'.
A top BTRC official said an operator can sell up to 100 million 11-digit numbers using one series.
The '010', '012', '013', and '014' series are unused now.
The operators have the opportunity to sell a number if it remains unused for 18 straight months.