There were 455 pupils attending schools in Northern Ireland last year who were not residents of the province, the Belfast Telegraph can reveal today.
According to figures released by the Department of Education, the majority of non-domiciled pupils attending schools in Northern Ireland were in the Western Education and Library Board.
While the Department said it was unable to state the country of residence of the 218 pupils attending WELB schools, the figures are likely to spark further controversy in the ongoing 'grannying' row and issue of oversubscribed schools in Northern Ireland.
The Department of Education released the figures in response to an Assembly question tabled by the DUP's Iris Robinson, who asked for information on the number of children resident in the Republic of Ireland but enrolled in schools in Northern Ireland in 2006-07.
In response, Education Minister Caitriona Ruane - who sends her children to a school in Northern Ireland from her home address in the Republic - said that the information on the specific country of residence of pupils enrolled at schools in the province is not collected.
However, she was able to reveal that only schools in the North Eastern Education Library Board had no pupils resident in other countries, while 137 non-domiciled pupils attended schools in the Belfast Board area in 2006-07.
There were 92 non-domiciled children attending schools in the Southern Education and Library Board and eight in the South Eastern Board area during the same period.
Responding to the figures, Mrs Robinson said: "The numbers of children involved are very high, particularly in the Western Board area.
"Some in the post-primary category will be boarders from overseas, but this is unlikely to be the case with primary school children. The fact that the figures are higher for areas close to the border would indicate that it is students from the Irish Republic who are involved primarily.
"These figures, of course, will not include those from the Irish Republic who are using false or spurious addresses within Northern Ireland in order to obtain places at particular schools for their children. As a party we are not opposed to practical co-operation with the Irish Republic, where it is in the interests of the people of Northern Ireland.
"However, it appears that some people are seeking to take advantage of our system. The welfare of the Northern Ireland taxpayer must be our prime concern."
The practice of 'grannying' - applied to people living in Donegal who use grandparents' addresses in Londonderry to gain admittance for their children at a school in Northern Ireland - has come to prominence in recent months with a high profile legal challenge in which three sets of parents fought a successful battle for their daughters to be allowed to take up their places at St Cecilia's in Derry.
The Donegal girls had been offered places at the school that were withdrawn when the Department of Education refused to increase an admissions cap.