The major price differential between the North and the South, allied to an increase in petrol smuggling, has led to the closure of 48 petrol stations in the North in the past two years, according to the Petrol Retailers' Association there.
The association has been campaigning for harmonisation of petrol prices throughout Ireland. A spokesman said Northern motorists were paying up to 90p more for a gallon of petrol than their counterparts in the South.