The Government and the Irish Congress of Trade Unions have condemned anti-Nice Treaty campaigners, following allegations that "floods" of Eastern European workers will move to Ireland after the European Union enlarges.
The No to Nice Campaign spokesperson, Mr Justin Barrett, vowed on Tuesday to put immigration to "the fore in people's minds" in the run-up to the October referendum.
In a statement yesterday, ICTU said the allegation was "a blatant attempt to frighten voters" into voting No. "Talking about 'a flood' of workers from East European countries is crude scaremongering, without any basis or justification whatsoever.
"If elements of the No campaign are prepared to descend to such depths and scrape the bottom of the barrel for spurious threats to scare the electorate, then the prospects for a reasoned debate on the Nice Treaty are remote", said ICTU.
There was now "an immediate onus" on other No campaigners to dissociate themselves from the No to Nice Campaign's tactics and to reassure people that "fear of mass immigration is not a reason for voting against the Nice Treaty," the trades union body declared.
In the light of the evidence available, ICTU said it was satisfied that there was no significant threat to employment or to wages and conditions posed by Central and Eastern European workers.
Ireland is one of three EU states which have agreed to allow workers from these countries to travel freely following enlargement.
The others have imposed barriers that could last up to seven years.
Immigrant workers coming to Ireland would not be able to undercut Irish workers, ICTU said, since they would be entitled to the same pay and conditions as people already working here.
A balanced immigration policy would be fair to immigrants and help the Irish economy, while also respecting the Government's right to control the numbers entering the country.
"In the very unlikely event of problems arising from immigration after enlargement, Ireland, like all member-states, retains the ability to take effective steps to address them," said ICTU.
The Minister of State for Foreign Affairs, Mr Dick Roche, called on the Green Party to publicly dissociate itself from the "xenophobic" remarks made by Mr Barrett, and earlier by the National Platform's Mr Anthony Coughlan.
"The Green Party should clarify its position. Does it support the commentary of Mr Barrett and Mr Coughlan?
"If not, the Green Party should say so," Mr Roche declared.
He said Mr Coughlan's "doom-laden prophecies have always been wrong in the past and there is no reason to believe him now.
"There is more than sufficient provision in the existing EU law to protect Ireland's position," Mr Roche added.
Last week, the leader of the Green Party, Mr Trevor Sargent, said he did not agree with Mr Coughlan's immigration views, but he did not criticise the National Platform spokesperson for issuing them.