Christmas postal services are unlikely to be affected by strike action at An Post, but the one-day stoppage set for next week will lead to delays in social welfare and pension payments.
The 24-hour stoppage set for next Wednesday is due to go ahead despite unions and management at the company agreeing today to hold talks.
CWU general secretary Mr Steve Fitzpatrick
The dispute is over plans to close the loss-making SDS parcels and couriers division with the loss of 270 jobs as part of a plan to restore financial stability to the overall company.
"The day of protest next Wednesday is the first step in a vigorous campaign of action by this union and its members to rescue the national postal service," Communications Workers Union (CWU) general secretary Mr Steve Fitzpatrick said.
Further industrial action was inevitable, he added, if employees were not consulted on the future of An Post. The union is also demanding pay rises to meet increases in the cost of living.
Thousands of pensioners and other welfare recipients face delays in getting payments next week if the strike goes ahead.
The action will close down services on Wednesday, but could cause knock-on disruption to payments on Thursday and Friday, An Post warned.
"The situation in An Post is that we have major financial and business problems," said Mr Larry Donald, chief operations officer of An Post. "This is an industry that is suffering decline, so its core products and the demand for them is actually reducing.
"It is also a company with very high cost structures and serious change is needed - obviously there is resistance to that."
Mr Donald said that Christmas post would not be affected if the industrial dispute was just contained to the 24-hour stoppage next Wednesday and festive working arrangements went ahead as planned.
An Post said the announcement of the one-day stoppage was "extremely disappointing".