The trade union is bringing their case back to the Labour Court.
SIPTU has hit out at Tara Mines management, condemning their "abject failure" to agree a facilitation process aimed at reopening the mine.
The union says management had originally agreed to an independent process to resolve issues but has now reneged on that commitment.
Workers at the mines have been temporarily laid off for 130 days, which the union describes as a "national scandal".
SIPTU Sector Organiser, John Regan says the dispute has now gone back to the labour Court:
Tara Mines says a reference to the Labour Court isn't "necessary at this stage."
However, it says it will participate fully in the process, after SIPTU today revealed the dispute between staff and management at the Meath mine has gone back to the Labour Court.
The union says management has reneged on an agreed plan for an independent process to resolve issues.
Tara Mines says it hopes to resolve the issues surrounding those arrangements swiftly, and it's doing everything it can to get the site back up and running as soon as possible.
In a statement to Midlands 103, Tara Mines says:
"We are doing everything we can to re-open the mine as soon as possible. We are working on the development of a rescue plan, designed to address operational challenges at Tara Mines, and want to work together with the group of unions on this.
These operational challenges were one of the factors that led to the decision to temporarily enter care and maintenance. Ultimately the re-opening of the mine will be influenced by external market conditions, but the development of a rescue plan, which is within our control, will help to expedite the re-opening process.
In order to help develop the plan, we agreed to hold a series of workshops attended by management, employees and union representatives. We believed the arrangements for the workshops were agreed by all parties, and we have agreed that the workshops should have an independent facilitator. We hope to resolve the issues regarding these arrangements swiftly, as we believe the workshops will be of benefit in the development of a rescue plan.
We will continue to engage with the group of unions. We do not believe a reference to the Labour Court is necessary at this stage, although we will participate fully in the process."