Concern is growing for the future of 200 jobs at the Irish Fertiliser Industries plant at Marino Point in Cork Harbour.
The board of IFI was told today that negotiations to sell the company had broken down.
Workers fear the IFI plant in Cork will be shut down in order to secure the future of the company's other plants at Arklow and Belfast.
IFI is the country's only manufacturer of agricultural fertiliser.
However a spokesman for IFI said tonight that the company is considering a number of options for its future.
The spokesman stressed that no decision had been taken regarding the closure of any of the plants.
He said work on these options will continue over the coming weeks and news of developments would be communicated to the shareholders and to the workforce in due course.
The company has suffered over the past two years because of a glut of fertiliser on the European market. Prices have dropped and demand for IFI's products has fallen by 10%.
In August, IFI's management sought funding of around €25m from its shareholders, the Government and the chemical company ICI, but that request was refused.
IFI management then looked at other options, including the possibility of selling the company. Negotiations got underway with at least one interested party, but these have broken down.
Workers at IFI in Cork fear the plant there is about to be shut down, whether or not the company is sold because the ammonia they produce for the plants at Arklow and Belfast can be bought cheaper on the open market.
All sides are now agreed that the future of the plant at Marino Point looks grim. If IFI is not sold, it is accepted that it could only survive with radical cutbacks. Cork would be first on the list.
Even if the company is sold, whoever buys it will have the option of getting ammonia on the open market cheaper that it can be produced in Cork.
