US based Southern Copper's Cuajone and Toquepala copper mines, and its Ilo smelter in Moquegua region are operating normally after workers ended a two day strike.
The company said in a release that the company was able to maintain production levels during the strike on December 24 and 25 by implementing an emergency.
Union representative Ricardo Juárez told BNamericas that the workers, however, continue to threaten an indefinite strike in January should SCC not offer an increase in wages and better working conditions.
The company has not changed its initial offer of a 5.5% wage increase. The workers are asking for a 15% raise.
Mr Juárez said that a union meeting on December 28 will determine the strike plan, which will then need to be approved by the Peruvian labor ministry.
SCC also said that it has started legal action against the labor authority to determine the legality of the initial two day strike.