Organisations working with asylum-seekers have questioned the legality of new residency arrangements for parents of Irish-born children and are seeking legal advice.
They also fear some parents may miss their last opportunity to apply for residency because of difficulties obtaining passports.
Under revised arrangements the non-national parents of children born here before January 1st can apply for residency. However, they must "accept that there is no entitlement to family reunification".
Ms Aisling Reidy, director of the Irish Council for Civil Liberties, said there were numerous cases of parents who had left other children or spouses behind when they left their countries. "We have concerns about its legality in terms of the State's obligation under the Constitution to the family, under the European Convention on Human Rights and the UN Convention on the Rights of the Child," said Ms Reidy.
Concern is also being expressed over the need to send the parents' passports with each application because of the difficulties some of them are having in getting passports from their embassies here.
There can be a long wait for the passports; costs are said to be prohibitive; and some people have to travel to Britain, giving rise to added costs and the need to obtain leave to leave the jurisdiction.
A Nigerian father said he had applied for a passport at the Nigerian embassy last month. "I applied on the Internet and put in all the requirements. It said I would be called for an interview, but it has been four weeks and I haven't heard yet. They said also it would be €400 for a passport which is a very high amount. I am on the direct provision so I get €19.10 a week."
A spokeswoman for the embassy confirmed the cost at about €400.
Ms Mary King, of Dún Laoghaire Refugee Project, said she had come across numerous such cases. "The question is will these people be forced to go to moneylenders?"
Mr Peter O'Mahony, of the Irish Refugee Council, said he hoped the deadline for applications, which is March 31st, will be extended.
A Department of Justice statement said if the right to family reunification was not renounced, "the application will not be considered". It said original passports must be supplied with each application.
