Mandate Trade Union has criticised the decision by Marks and Spencer to open some of its smaller stores around the country today - while more than 2,000 workers are on strike.
The union claims the company is using temporary seasonal staff in a "crude fashion" to effectively break a legitimate industrial dispute.
Athlone Marks and Spencer branch open despite strike action http://t.co/i2aPNvpHWb— Shannonside FM News (@shannonsidenews) December 7, 2013
Workers walked off the job in a row over pensions, a cut to their Sunday premium pay and the scrapping of the Christmas bonus.
Two further days of strike action are planned for December 12 and 20.
Management say they want to re-open "meaningful negotiations", but Mandate assistant general secretary Gerry Light said that he does not believe their requests are genuine.
"On the one hand, they're saying that they want to engage in meaningful negotiations, yet in a press release last night they said that they were going to, regardless of the industrial action today, proceed with their plans," he said.
"Now, it's either one thing, or the other."
Of the company’s 17 stores in the Republic, two – in Athlone and Navan - were able to open, and then only for limited hours.
At the flagship store on Henry Street in Dublin, staff holding banners staged a picket and urged shoppers to sign a petition supporting their stance.
Trade union Mandate has insisted workers did not want to strike during the festive season but claimed management had left them with no choice.
While Mandate represents the majority of the 2,300 M&S staff working in the Republic, 140 members of trade union Siptu who work for the retailer are also taking part in the action.
Staff voted overwhelmingly in favour of a wave of festive walk-outs last month in the deepening row with bosses.
As well as changes to a pension scheme, the unions oppose a number of other measures proposed by management, including a reduction in the Sunday and public holiday premium paid to staff, the scrapping of the Christmas bonus, and a reduction in the number of section managers.
Gerry Light claimed the cumulative effect of the planned cuts was too big a burden for the workers to pay.
“Let us be very clear about this; our members do not want to be out on the streets and in shopping centres picketing their employer,” he said.
“These are very loyal workers, some of whom have worked for30-odd years for this company.”
Marks and Spencer, which disputes many of the claims made by the unions involved, accused them of misleading employees and customers to gain support for the strike.
A spokeswoman said the company had to make some “very difficult decisions to protect the long-term good of our business in the Republic of Ireland”.
She added: “We will not be put off course by the threat of industrial action. The impact of diverting now would be hugely detrimental to our customers, our employees, and our business and put our plans for future investment in doubt.
“We hope that the unions will come to realise this and agree to re-open meaningful negotiations to prevent any further disruption and inconvenience for our customers and employees.”
Mandate claimed the stores that opened were only able to do so with the use of seasonally employed staff – a move it branded “provocative”.
M&S did not provide detail on the status of staff who worked in the Athlone and Navan stores today.