Government has rejected Konkola Copper Mines (KCM)'s move to lay off 1,529 workers.
The mining firm has started downsizing labour which would see 1, 529 miners lose their jobs with immediate effect.
But Labour and Social Security Deputy Minister Rayford Mbulu said the company had not notified the Government as required by law.
Mr Mbulu said under cap 268 of the laws of Zambia, a firm should give notice to the Government before embarking on any redundancies.
Mineworkers Union of Zambia president Nkole Chishimba expressed disappointment with KCM management over its decision to downsize labour especially that the company had not communicated this to key stakeholders contrary to its claim.
"We are calling on Government to quickly come in and investigate why the company is behaving in this manner. This is a sign of failure to run the mine because if it's resorting to retrenchment then the future of the mine is not certain," Mr Chishimba said.
According to KCM, the move is in line with its continued restructuring of operations.
The company said it was moving towards mechanisation and automation in view of the decreased copper grades at some of its mines.
Company chief executive officer Kishore Kumar announced the development yesterday in Kitwe, adding that the process of laying off the 1, 529 employees had since commenced.