Solid Energy is expected to make an announcement about its future tomorrow.
Staff have been called to meetings in four locations around the country, including Westport, Southland and Waikato tomorrow morning.
The state-owned miner is expected to make a public announcement in Christchurch at midday.
The company has told staff it is looking at three options - an arrangement that would allow the firm to continue trading, some kind of controlled sell-down, or liquidation.
In April, Finance Minister Bill English ruled out the Government putting more money into the company, which is struggling to service $320 million of debt.