ZCCM-IH launched action in Oct 2016 to sue First Quantum over claims that the company borrowed $2.3bn from copper mining subsidiary without informing them.
Transport Minister Brian Mushimba said there was evidence of huge imbalance between use of road and rail sector leading to the underperformance of railways.
The Russian state-controlled diamond miner increased fourth-quarter production by 6 percent year-on-year to 10.1 million carats as a shutdown at its Mir mine was offset by higher output at other assets.
The approvals will allow the company to modify its original expansion plan, already permitted and now 44 pct complete, which seeks to add another mine level.