The jobs crisis worsened yesterday as an electronics group announced 170 lay-offs and the future of 119 workers at two other companies was thrown into doubt.
Telecoms manufacturer Volex is shutting its Castlebar, Co Mayo, factory, with production shifting to eastern Europe.
Question marks also hang over a north Cork electronics firm employing 49, which has gone into liquidation, and a Kilkenny meat processing plant with 70 workers that has closed temporarily, blaming difficult trading conditions.
The pull-out by Volex, which employed 1,000 in Castlebar at the height of the 1990s boom, in favour of low-wage economies underlines how far the Republic's competitiveness has diminished over recent years.
The Tánaiste, Ms Harney, said the move was a "devastating blow" for the town, highlighting the huge challenge facing the Government as it attempts to stop the State haemorrhaging further multinational investment.
Although Volex has pledged to keep its European headquarters in Castlebar and will retain 70 staff, locals have reacted angrily to the closure announcement.
Having laid off 620 workers in the past three years, Volex had promised there would be no more job cuts, said local SIPTU official Ms Martina Weir.
"We feel betrayed, let down," she said. "\ were utterly loyal and all they got in return was the sack."
Blaming the telecoms slowdown, Volex Europe managing director Mr Steve Cowman said employees had been aware that Castlebar was struggling to turn a profit.
Fine Gael leader Mr Enda Kenny, a local TD, said the closure was an indictment of the Government's inability to steer the economy through the downturn.
He said: "The workers at Volex and their families are today paying the price for years of Government mismanagement of the economy. They join the workers of Guinness, Tayto, Navan Carpets and countless others, who have had to endure the loss of their livelihoods as a price for Government's reckless management of public finances, its unwillingness to tackle the vested interests that are driving up costs and its inability to deliver new infrastructure projects on time or to tackle the failure to deal with our uncompetitive economy."
Elsewhere, it was announced that north Cork electronics company Keytech Enclosures, which employs 49, has gone into liquidation. It is hoped the firm, a producer of telecoms and computer parts, can be sold as a going concern.
In Kilkenny, workers at Honey Clover Meats in Freshford protested outside the factory yesterday amid growing uncertainty over its future. Some 70 jobs at the meat processing plant are in jeopardy. Last month the company announced a temporary closure because of trading difficulties.
In nearby Kilkenny city, there are fears Kilkenny Castle, one of the region's major tourist attractions, could be forced to shut as a result of a labour dispute. Some 18 staff have voted for a strike in a row over work conditions.
