Almost 6,000 drivers from the Republic have been hit with parking fines from Northern Ireland's authorities after new rules were introduced early this year aimed at cutting down on cross-border offences.
Before 1 January last, drivers from the south who committed offences in the North – and vice versa – could not be fined because there was no common legislation or agreement between the two jurisdictions.
It had been estimated that drivers from the Republic who parked illegally in Northern Ireland had avoided fines worth £1.7m (€2m) since 2006.
Since the new laws came into effect, 5,713 fines have been issued to southern-
registered vehicles, worth about €420,000.
However, to date the Northern Irish Roads Service has only received £89,067 (€108,472) in fines from Republic-registered vehicles as almost 60% of the drivers who received fines failed to pay. They now face further sanctions.
"The longer a driver leaves it, the higher their fine will be. However, if Republic of Ireland drivers pay within 14 days there is a 50% reduction. We are pursuing the rest of the fines," said a spokeswoman for the Northern Ireland Roads Service.
Authorities here have agreed to share vehicle registration details to ensure offenders can be pursued through the courts.
In the Republic, border counties such as Donegal had been losing revenue running into hundreds of thousands of euro because drivers from the North who incurred fines could not be pursued across the border.
Transport minister Noel Dempsey announced the agreement between the two jurisdictions in March.
It is part of a pilot programme which is due to complete this November.
Speaking at the time, Dempsey said: "This is another important step in road safety and traffic enforcement and one that we are all strongly committed to.
"The data will be transferred using the highest level of security and will be monitored in each jurisdiction through an agreed audit regime. We have successfully overcome potential difficulties regarding data privacy and security issues in the pursuit of cross-border traffic offenders."
Meanwhile, Northern Ireland motorists evaded €1.3m of toll road charges in the Republic, an issue which is also being tackled in the cross-border initiative.