Subscribers to O2 Ireland can sign up for a new all-Ireland mobile tariff from September, in a move designed to alleviate the costs of cross-Border roaming.

The service will enable consumers to make and receive calls in Northern Ireland on the O2 UK network for the same price as they make calls in the Republic.

O2 estimates the savings on mobile costs could be up to 70 per cent, although the tariffs will not apply when users make calls to British mobile phones or to numbers with the prefix 0044.

Subscribers will be able to sign up for the all-Ireland service as one of O2's existing Choices price plans, each of which costs an extra €7.50 per month. However, the first additional offering on the Choices plan is provided free.

Consumers and businesses based close to the Border have complained that they face excessive costs because they can automatically roam onto other networks when near the border.

O2 Ireland said yesterday it hoped the new tariff would increase cross-Border trade.