Almost 650 central and eastern Europeans were repatriated for free last year under a Government scheme aimed at assisting destitute immigrants.
The figures, which have doubled over the past year, come at a time when homeless agencies are expressing concern at the number of EU immigrants experiencing hardship.
As a result of welfare restrictions, many are not eligible for social assistance such as unemployment benefit on the grounds that they are not habitually resident here.
Figures provided to The Irish Times by the Department of Justice show the majority of immigrants who were assisted in returning home were Poles (380), followed by Slovaks (98), Latvians (47), Hungarians (46) and Czechs (33).
The numbers availing of the repatriation scheme have climbed dramatically since the 10 former accession states joined the EU in May 2004. The Reception and Integration Agency (RIA), which operates under the Department of Justice, says it repatriated 149 destitute EU migrants in 2004, 318 in 2005 and 646 last year.
The scheme is open to any citizen of a former EU accession state, and certain other "special-case" EU nationals, who find themselves destitute during their time in Ireland. The repatriations cost the State just over €300,000 last year.
Groups such as Emigrant Advice say immigrants tend to experience hardship for a range of reasons such as having inadequate savings, poor English language skills and being exploited by Irish employers.
Joe O'Brien, the organisation's information and outreach officer, said social assistance restrictions aimed at preventing "welfare tourism" meant there was often no safety net for migrants who ended up homeless.
"We're concerned that these restrictions are further marginalising a section of society that is already in a vulnerable position," Mr O'Brien said. "It's a lot like the Irish in London 10 years ago. We're coming across migrant workers whose employers aren't paying their PRSI contributions, so if they lose their jobs they don't have access to social assistance."
Homeless agencies such as Trust say the majority of people seeking help from them are now EU immigrants.
Alice Leahy, director and co-founder of Trust, said the Government needed to act immediately in order to prevent the problem from growing further.
"It's something that, unless dealt with now, will certainly get worse. The people we're seeing are just like the long-term Irish homeless: they suffer from malnourishment and poor health," she said.
Emigrant Advice says the problems could be eased if the Government relaxed restrictions on social welfare for EU migrants.
