Redundancies increased 40.7 per cent in August compared to the same month in 2002, according to new Government statistics.
There were 2,138 notified redundancies last month, compared to 1,520 12 months previously, according to the Department of Enterprise, Trade and Employment.
However the number of redundancies was the lowest since May.
As expected, the manufacturing sector was hit heaviest with 821 notified redundancies during August, followed by distributive trades (358), financial services (308) and other services - including IT - (278).
The surge in notified redundancies comes less than a week after the quarterly national household survey showed the labour market proving more resilient than expected, with total employment climbing by 28,400 in the year to April.
This brings the total annual rise in unemployment, as measured by the survey, to 4,200 - significantly fewer than the 10,000 average annual rise in the live register in the same period last year, leaving the jobless rate holding steady at 4.6 per cent.
The figures carry a health warning - they refer only to proposed redundancies, not to actual job losses. Redundancies notified during a month may relate to cases that, on examination by the Department, are found not to be qualified redundancies
Opposition politicians accused the Government of failing to respond adequately to the decline of traditional industries, particularly in the manufacturing sector.
"There are less people at work in the manufacturing industry in Ireland today than when Bertie Ahern became Taoiseach," said Labour finance spokeswoman Ms Joan Burton.
"There is much anecdotal evidence of of labour shedding in certain sectors such as tourism. This will put even more pressure on tax revenues over the next few months," she added.
Meanwhile, new figures show that the euro-zone jobless rate held unchanged at a three- and-a-half year high in July - the latest evidence of improving sentiment among euro-zone member states.
The bloc's jobless rate was steady at 8.9 per cent in July.Spain had the highest unemployment rate in the region at 11.4 per cent.
