The chairman of the education committee said he was "totally opposed" to children from socially disadvantaged areas continuing to be given priority for pre-school places, on 6 June 2012.
Mervyn Storey of the DUP was responding to a briefing given to the committee by Department of Education officials on changes made to the admissions process.
Linda Wilson from the department said that although the July/August birthday criteria would be removed from 6 July, those children from socially disadvantaged backgrounds and those with special educational needs would still be given priority when it came to obtaining a pre-school place.
Mr Storey said he would not accept the revised regulations for pre-school admissions as they currently stood.
"Yes, there have been advances made in pre-school provisions, but I see nothing in this paper that addresses the issues of working parents or single parents who have problems with access," he said.
"We are now creating another disadvantaged group but because they can't tick the boxes, they are going to remain disadvantaged and the department's attitude to that is 'well, tough'".
Miss Wilson agreed the socially disadvantaged criteria was out-of-date and needed to be amended, however, she defended it being retained until a greater review was carried out.
"There is strong evidence that children from socially disadvantaged backgrounds and low socio-economic homes do start school behind and do stay behind throughout their academic career," she said.
"There is strong research and educational evidence that they do need additional help."
Miss Wilson said children with July and August birthdays were initially favoured when pre-school provision stood at 45% and there were concerns that if these children failed to secure a place, they would have no education experience until their 5th birthday.
However, she said this criteria could no longer be defended as there was now "broadly sufficient provision to meet demand".
This was challenged by Mr Storey who asked how the department could hold this view when people living in Ballymoney were offered pre-school places in Larne.
Lagan Valley MLA Trevor Lunn of the Alliance Party also said Education Minister John O'Dowd's recent announcement that the parents of only 24 children who applied for pre-school places had not managed to find a place was "completely unbelievable".
"It just doesn't seem credible. I'm sure there are more than 24 in Lisburn," he said.
Independent MLA David McNarry also briefed the committee on the community use of schools, and representatives from the Association of Professionals in Education and Children's Trust (PROSPECT) spoke on a review of teacher education.