He said: “As a result of our combined membership of the European Union, people in the North and the South no longer pay mobile roaming charges on calls, texts or data.
“And even before that, European Union directives saw a cap on the costs for roaming charges.
“Theresa May’s order that Britain should leave the digital single market may mean that she has to pay more on a trip to the south of France but it will have a significant impact on people living in border communities or those who cross the border for work here.
“People living in border communities are aware of how often their phone switches to a southern network, depending on which phone mast they’re closest to.
“They have genuine cause for alarm at the prospect of a return to roaming charges, especially those in a non-EU state.
“A white van man living in Strabane could soon face a call from Dublin costing the same as one from Dubai –around 30 times the cost before roaming charges were abolished.
“And the difference in mobile data could be even more unsettling. Surfing the internet on your phone in Navan could return to the same cost as in New York – over 100 times more expensive than before charges were scrapped.
“The British Government needs to get real about dealing with the Irish border. The EU has proposed workable solutions based on agreement from the last phase of talks.
“If Theresa May wants to diverge from her word, then her government must come forward with proposals of its own.
“The vacuum of leadership can’t continue,” added Mr McCrossan.