Peru unions say ready for nationwide mining strike

LIMA, May 6 (Reuters) - Unions at mines throughout Peru are ready to strike next week to demand better labor benefits, the head of the country's biggest federation of mining unions and local union bosses said on Tuesday.

"We have 33 unions supporting us," said Luis Castillo, the federation's leader. "We will go on nationwide strike on May 12 no matter what."

Peru is the world's leading silver producer, ranks second in copper and zinc, and fifth in gold, according to government data.

Castillo has said the federation has formally filed documents advising the government about the strike.

Unions expected to strike include those at Southern Copper (SPC.LM) (PCU.N), Antamina, Doe Run Peru, Shougang Hierro Peru (SHP.LM), Atacocha (ATA.LM), and Milpo (MIL.LM), among others.

Unions at the Tintaya and Cerro Verde (CVE.LM) are set to meet later on Tuesday to decide about supporting the walkout.

Twice last year unions went on nationwide strikes, which partially cut output at some mines and pressured international metals prices.

The strike next week, like the previous ones, would aim to pressure the government to would lift caps on profits that mining companies share with workers.

They also want the government to change rules for early retirement, to clamp down on outsourcing by companies, and to give workers the right to enroll in state-run pension funds.

Unions also want work days changed to eight hours a day, instead of 12 hours a day. (Reporting by Teresa Cespedes, Translating by Terry Wade, Editing by Marguerita Choy)