Workers at a US-owned copper mine in Peru launched a wage strike Friday, heightening pressure on the market for the key commodity already hit by a similar stoppage in Chile (Stuttgart: 704599.SG - news) .
Some 1,200 workers downed tools at the southern Cerro Verde mine, majority-owned by Arizona-based Freeport-McMoran, said union spokesman Rommel Arias.
The miners are demanding special benefit payments to protect their incomes against a downturn in copper prices, and better working conditions.
"We have ended discussions with the company and no agreement has been reached," Arias told AFP.
"The strike starts at 7:30 am on Friday morning (1230 GMT)."
Mining sector consultant Jorge Manco calculates that production at Cerro Verde reached half a million tonnes last year, making it Peru's biggest copper mine.
Strikes at copper mines have raised concerns on international markets for the metal, a key component in electrical wiring.
Some 2,500 workers at the world's biggest copper mine, the Escondida site in Chile, have been on strike for a month for higher pay.