Meat processing company Olhausen is to close its three plants in Dublin and Monaghan with the loss of 160 jobs.
More than 100 of those employees work at the company's headquarters in Blanchardstown.
The Olhausen company is well-known for its sausages and has been operating in Ireland for over 100 years.
It also supplies a range of pork, ham, turkey and salami products to the retail and catering trade.
Apart from its Blanchardstown headquarters, it has production facilities in Coolock in Dublin and another in Lough Egish in Co Monaghan.
Ulster Bank has appointed receiver Jim Hamilton of BDO to the company.
SIPTU, which represents 100 employees, said staff were told this morning that the firm is no longer a going concern and has ceased trading at all three factories.
The union confirmed that the receiver has agreed to pay outstanding wages to all 160 employees. They will also be entitled to statutory redundancy.
Minister for Jobs, Enterprise & Innovation Richard Bruton has said he is hopeful that there will be interest from investors in the company.
Mr Bruton said the company had been largely confined to the domestic market, which had experienced severe difficulties.
"I believe that this company and what it has built will attract interest from investors, and hopefully that's what will come out of this receivership," he said.
However, SIPTU said it does not believe a buyer will be found.
Speaking on RTÉ's News at One, Colm Casserly said that the case presented to the Union is that the company will "probably be sold off piecemeal".
He said the receiver appointed by Ulster Bank had told them that efforts had been made made to find a buyer but that that was looking increasingly unlikely.