(Bloomberg) -- Glencore Plc’s zinc and copper production fell in the first quarter as the company curbed mine output following last year’s slide in commodity prices. It maintained output forecasts for all products except oil, which it reduced.

Zinc output totaled 257,100 metric tons in the three months through March, down 28 percent from a year earlier, the Baar, Switzerland-based miner and trader said in a statement on Wednesday. Copper output slipped 4 percent, while coal production declined 17 percent. The company cut its oil-output target by 300,000 barrels.

Glencore has said it plans to reduce copper output by about 7.5 percent this year and cut zinc supply by a quarter. Some of the biggest miners have been forced to shutter unprofitable operations, trim costs and sell assets to reduce debt in response to slowing demand from top user China. The Swiss firm, led by billionaire Ivan Glasenberg, has surged in London this year after ending 2015 as the second-worst performer in the FTSE 100 Index.

Glencore is the world’s biggest zinc miner and the move to reduce output of the metal is bringing the market closer to deficit. It’s the second-largest producer of refined copper and has suspended operations in the Democratic Republic of Congo and curtailed output in Zambia.

While copper output dropped because of curtailments in Africa, production was partly offset by increases in South America, the company said.

Glencore, valued at about 21.6 billion pounds ($31.4 billion), climbed 66 percent this year as zinc rallied 18 percent and copper gained about 5 percent.

In other commodities, Glencore’s nickel production advanced 16 percent to 27,600 tons as coal production fell to 29.7 million tons.

Peter Grauer, the chairman of Bloomberg LP, the parent of Bloomberg News, is a senior independent non-executive director at Glencore.

To contact the reporter on this story: Agnieszka de Sousa in London at To contact the editors responsible for this story: Lynn Thomasson at, Nicholas Larkin, Ana Monteiro

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