SIPTU said it will begin an intensive engagement with the management of Tara Mines in Co Meath on Monday to discuss alternatives to its proposal to temporarily close the facility and temporarily layoff 650 workers.
The company described the decision to suspend operations as "unavoidable" and said that the business was "cash-flow negative".
"Union representatives have demanded that management engage with us to look at alternatives to the proposed layoffs," said SIPTU Division Organiser, Adrian Kane.
"Management have now agreed to this position and we will endeavour in intensive talks which are to begin on Monday to work towards an outcome which will maintain the operation of this mine," Mr Kane added.
Minister for Enterprise, Trade and Employment Simon Coveney met with management and worker representatives at Tara Mines yesterday.
Following the talks, he said the company is in a very serious and difficult financial situation.
Mr Coveney called for detailed engagement between management and the union and said the Government's focus was on supporting workers and their families, and finding a way for Tara Mines to reopen.
Boliden said losses at Tara had been brought about by a combination of factors, including a decline in the price of zinc, high energy prices and general cost inflation.
Management said they could not be definitive about how long the period of suspension would last, but that the company believed it is temporary.
In a statement, Boliden Tara Mines said it would have further engagement with unions next week.
"We will listen to the unions' proposals and continue to converse with them as we have done over many years," the company said.
"The situation that has emerged in relation to the company's finances is unsustainable and we had to take action to stem the cash outflow," the company added.
