A decision is expected today on whether there is a basis for proceeding to substantive negotiations in the Luas pay dispute.
Yesterday, SIPTU and Transdev engaged in separate discussions at the Workplace Relations Commission to see if full talks can begin.
The row centres around a pay hike of up to 53%.
Last week Luas drivers engaged in a 48-hour strike with further industrial action planned for March 8, as well as St Patrick's Day on March 17.
SIPTU spokesman Eoin Reidy says that the Union is prepared to negotiate.
"We've always said that that's an opening position, we've always said we're prepared to negotiate, we've always said we're prepared to moderate that and compromise," he said.
"That position has always been the case, the problem up to now is we haven't had a partner in the employer to negotiate with.
"We hope that changes, but it remains to be seen."
Transdev has previously said that the pay claims would cost the company more than €20m over five years.
Gerry Madden from Transdev stated last week that Luas drivers already enjoy some of the best pay and conditions in the world.
“Owen Reidy has been invited, on numerous occasions, by myself and others, to seriously look at the claim,” he said.
“We, as an operator, Transdev, are in the business of running light rail. We’ve gone and looked at, not just in the countries where we operate but beyond that as well to find out if there’s any train drivers who earn better pay and conditions – we can’t find any.”