A meeting between Tara Mines management and unions before the Workplace Relations Commission has been suspended for the evening.
The parties were holding talks about the company's plan to temporarily suspend the Co Meath operation and lay off 650 workers next week.
Speaking following today's meeting, Adrian Kane, Divisional Organiser for SIPTU, said that they would meet at the WRC again tomorrow.
"I think it would be a fair comment to say there was still a considerable distance between the parties," he added.
Boliden, the owner of Tara Mines, had announced that the operation would be suspended and placed into "care and maintenance" from the 14 July.
It has not been able to give a definitive time frame for how long this would last, but said it believed the situation would be temporary.
SIPTU says that the company has yet to present a "satisfactory outline" of terms and conditions for workers during this period.
Sector Organiser John Regan said that Boliden "has yet to present to unions with a satisfactory outline of what it envisages providing its employees in terms of a retainer and other payments in the event of a lay off".
He said this was a "completely unacceptable situation" and that it "does not bode well in terms of where this dispute is heading".
The company said the losses have been driven by several factors including a decline in the price of zinc, high energy prices, general cost inflation and operational challenges.
Today's meeting at the WRC follows talks with Government yesterday.
Union representatives met Minister for Enterprise Simon Coveney and Minister for Justice Helen McEntee to discuss the situation.
Mr Kane earlier said it was clear that Government was committed to exploring what financial assistance it can provide to the mine.
However, he said it was "extremely unlikely" any measures would be in place by the 14 July, the date the mine is set to close.
Mr Kane said that due to EU prohibitions on certain types of State aid, this will be a "complex task".
"The meeting was called by unions in order to make clear to the Government that measures must be introduced to safeguard the livelihoods of our members and ensure the long-term future of Tara Mines," said Mr Kane.
"It was clear from the meeting that the Government is committed to exploring what measures it can take to provide financial assistance to this essential economic asset.
"However, due to EU prohibitions on certain types of state aid this will be a complex task and it is extremely unlikely any measures can be in place prior to the scheduled temporary closure of the mine on 14 July."
Unions also raised the issue of enhanced social protection measures for the workers in the event of being laid off and said that Government has committed to continued engagement on these matters.
SIPTU has called on the Government to expedite measures to protect the livelihoods of the workers and the long-term future of the mine.
With additional reporting by Brian O'Donovan
