Labour has accused the Government of financial sabotage and economic vandalism with comments about Solid Energy.
Finance Minister Bill English has said that the Government's support for the state-owned company is not unlimited.
He said the Government is waiting to see whether talks with Solid Energy's banks will come to some agreement.
Labour State-owned enterprises spokesperson Clayton Cosgrove said such comments jeopardise attempts to safeguard Solid Energy's future.
He told Morning Report it is impossible to create confidence among lenders if the Finance Minister is not publicly supporting the comany.
Mr Cosgrove said Solid Energy needs to concentrate fully on its core business of coalmining in order to secure its future.