Trade union Mandate has said that "substantial" pay rises are needed to address the issue of low wages in the retail sector.
The union's general secretary John Douglas said that increases in flat rate pay, rather than relying on the percentage increases provided for under social partnership, would be necesssary to deal with the issue.
He also warned that the union "would not entertain" any calls for wage restraint from low paid workers and urged the introduction of a new tax credits system for such employees.
New research commissioned by the union has found that despite the growth in retail sales in recent years, pay in the sector did not reflect its performance.
According to the research document
End Low Pay, shop assistants are currently earning an average of between €15,225 and €22,721 per annum. In large multiple stores, the average starting wage is €9.09 per hour, rising to €13.57 an hour after 10 years of service.
The sector currently employs more than 310,000 workers - some 15 per cent of the Irish workforce.
"In 2007, the growth of retail sales by volume in Ireland was five times that of the Eurozone, while the value of retail sales grew by almost 7.5 per cent in 2007. In fact, over the last three years, if earnings had been indexed to the value of sales, retail wages would have increased by 50 to 60 per cent more than the actual per cent increases received," said the report's author Camille Loftus.
"However, the wage increases received by retail employees have been determined by the percentage rates agreed in social partnership rather than the performance of the industry itself. While this may seem fair, in practice it means that retail workers, who are on low pay get much smaller increases in their weekly wage than those on higher rates of pay, meaning that the gap between high earners and low earners continues to increase."
The document called for the extension of flat rate increases to a wider range of low paid workers, claiming that the national minimum wage was at risk of becoming a ceiling for retail workers rather than providing a "floor" for wages. It said that those on the minimum wage benefited from flat rate increases in their hourly rate, which has meant that they received larger pay increases than many retail workers.
The union is also seeking the introduction of specific refundable tax credits for low paid workers, as they currently do not benefit from tax rate cuts because many pay no or very little tax.