More than 2,500 migrants are seeking jobs through Ireland's National Training and Employment Authority (FÁS) on any given day, recent information in Ireland suggests.
The figure provoked demands for a change in Government policy from both the opposition and Fianna Fáil backbenches.
A one-day snapshot survey of those accessing employment service offices found that 52% of the 5,000 seeking help were "non-nationals" from 94 countries, FÁS director general Rody Molloy told the Oireachtas Enterprise Committee.
Fine Gael enterprise spokesperson and committee member Phil Hogan said the news showed that far more people are migrating to Ireland in search of work than the Government realized.
"This is a very clear indication that the Government has no idea what the level of migration to this country is. We must look at migration policy and need to urgently put in place structures so we do know the true numbers.
"This revelation shows that there is a significantly higher number of people coming in from the EU looking for work than we hitherto realized, and suggests a significant number of migrants are in need of work," he said.
Mr. Molloy said he was "surprised" by the number of migrant workers seeking help, but added that it reflected major changes in the Irish economy. A definitive total for migrants turning to FÁS is unknown as many return to the agency on different days. Around 100,000 people are registered with FÁS nationally.
The FÁS migrant figures come in the wake of a clampdown forcing social welfare recipients to register for training or work placement after three months.
Despite the numbers needing help to find work, Mr. Molloy stressed that Ireland needs 500,000 more migrants in the coming decade.
"We need to get the right type of immigrants with the skills we need, and we will be competing with other countries for them," he told the committee.
Mr. Molloy said FÁS investigated whether foreign workers were causing job displacement and found that, although there had been a few instances, it was "not a substantial issue".
Fianna Fáil TD and Enterprise Committee member Ned O'Keeffe said the FÁS figures indicated a change in migrant policy was needed.
"We need to examine our whole immigration policy. There seems to be a major contradiction there. On the one hand, FÁS is saying we need half a million more migrant workers, and on the other... we seem to have 2,500 too many on any given day," he said.
"It looks to me as if there might be displacement of Irish workers going on."
SIPTU general president Jack O'Connor said job displacement was caused by employers trying to exploit the situation and not by migration.
Migrant workers from EU nations are entitled to welfare benefits after being resident here for two years, said a Social and Family Affairs Department spokesman.
A spokesperson for Enterprise Minister Micheál Martin said: "Ireland has a buoyant economy and needs migrant workers... Many of these people would be from accession states, and there is free movement of labor. Is Fine Gael saying it wants to stop that?"
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