Retailers say they are "nervously awaiting" the outcome of talks
Businesses in Dublin city say they saw a loss in sales following the weekend bus strike.
The latest round of strike action - on Friday and Saturday - saw a decrease in footfall and sales for city businesses.
Dublin city's Business Improvement District (BID), DublinTown, say footfall figures were down by 9% on Friday and 16% on Saturday.
Results from a survey conducted by the organisation showed 90% of traders saw a reduction in their takings.
The most common figure was a reduction in the region of 30% of sales - while 15% of traders say their sales were down by over 50%.
According to DublinTown, this level of sales reduction is "unsustainable" for many of their members.
"Already one-third of businesses are actively considering their opening hours due to the impacts of the bus strike," the group says.
DublinTown CEO Richard Guiney commented: "We are pleased to see a return of the parties to the WRC (Workplace Relations Commission) and hope that progress will be made in addressing the outstanding issues between the parties.
"City centre traders will be nervously awaiting the outcome of the talks.
"A prolonged strike, particularly one that stretches into the Christmas period, could prove too much for many businesses."
Management and unions are holding what has been described as "exploratory discussions" this afternoon, in a bid to resolve the ongoing pay dispute.
Further work stoppages are planned for Tuesday, Wednesday and Saturday of this week - as well as 10 more days next month.