Mobile operator O2 has taken action to help some mobile phone users from the Republic of Ireland avoid paying international roaming charges when they cross into Northern Ireland.
This is a serious issue for mobile phone users in both localities, who face much larger bills for calls or data services if they cross — or in some areas just get close to — the border.
Some mobile users who live close to the border have even been billed at international rates for calls made in their own house. Experts claim that the problem can be traced to the fact that the border, established in 1922, is not based around rivers or other physical boundaries.
O2 said on Wednesday that customers from the Republic of Ireland would no longer be charged for receiving calls while in Northern Ireland. It is also abolishing roaming fees for customers on monthly contracts who make calls to the Republic from Northern Ireland. Pre-pay customers will not enjoy this benefit, but will instead be charged a lower rate for roaming throughout.
O2 is also abolishing roaming charges for business customers between Ireland and the wider UK.
The operator claimed that these moves were a big step forward but there was anger that Northern Ireland users weren't included in these concessions.
"As it stands, only Southern companies and mobile users stand to benefit from these moves," said Dermot Ahern, Ireland's minister for foreign affairs. The Consumers Association of Ireland also hit out at O2's "limited" approach to the issue.
Other campaigners called on the other mobile operators to follow O2's lead, although Vodafone does offer an Ireland-wide tariff as well as its Passport product.
There is growing outrage over the international roaming fees levied by mobile operators. On Wednesday, the European Commission met with national regulators in an attempt to force changes.