TSTT is arguing that because it is a T&T-based mobile provider, it cannot control other networks in the region to influence roaming rates.
In a statement yesterday, state-owned TSTT said: "Because bmobile only operates in Trinidad and Tobago, it does not have unilateral control of any other network in the region to implement a non-roaming fee structure.
Nonetheless, through the association with LIME, bmobile negotiated several years ago an agreement with LIME whereby its post-paid customers do not pay to receive calls while they are in markets served by LIME," the statement said.
In November LIME announced plans to dramatically cut data roaming costs for customers traveling to the USA, but not within the Caribbean.
This comes as Jamaican Minister of Science, Technology, Energy and Mining, and president of the CTU, Phillip Paulwell, called for mobile networks across the region to follow Digicel's example and cut roaming rates.
On Wednesday, at the joint meeting of the 27th Executive Council and the 16th General Conference of Ministers, Paulwell called for the total removal of data and voice roaming charges across the Caribbean.
That meeting was part of the CTU ICT Week in Jamaica, from December 2 to 6.
TSTT said it would continue to negotiate better rates with LIME for customers.
"Likewise, when a postpaid bmobile customer makes calls in markets served by LIME, a uniform rate was implemented that was approximate to the cost of making a local call in T&T at that time. Bmobile continues to negotiate for better rates with LIME which will redound in even lower rates to its customers."
In August, Digicel announced it would be adjusting roaming rates for T&T and the Caribbean and in October implemented the decision.
The countries included are Anguilla, Antigua & Barbuda, Aruba, Barbados, Bermuda, Bonaire, British Virgin Islands, Cayman, Curacao, Dominica, El Salvador, French Guyana, Grenada, Guadeloupe, Haiti, Martinique, Panama, St Kitts and Nevis, St Lucia, St Vincent, Suriname, T&T and Turks & Caicos.
In October, Digicel told the Guardian: "The implementation process was a seamless one with Digicel's customers reacting very positively to the move. Many of our customers travel for business and other reasons and this is yet another avenue where they benefit from best value. They can now enjoy their trips and not be mindful of high bills."
Across the Caribbean, the cut in rates has been featured prominently in the news.
Digicel quoted Jamaica's Technology Minister as saying on August 7,2013, that "those roaming charges hinder affordable communication among Caribbean people, and as we move toward greater regional unity, we must take every opportunity to remove the barriers that keep us apart."
Digicel Cayman CEO Chris Hayman said: "So the idea of shutting off your phone from the network only to have WiFi is a thing of the past, once this system rolls out and our US partners adopt it. Digicel is always looking to respond to our customers' needs and we have been very happy with the demand for our current wireless broadband products and services," he said.