Production of cobalt, used in batteries for electric vehicles, reached 42,200 tonnes in 2018 while copper hit 1.453 million tonnes. Zinc output was mostly flat year-on-year at 273,300 tonnes.

Glencore's Katanga Mining unit in Congo ramped up in late 2017.

London-listed Glencore, which accounts for around a third of the global cobalt market, has benefited from its exposure to minerals needed for electric vehicles, including copper and cobalt.

But its shares, which fell 25 percent last year, have been weighed down by tougher mining laws in Congo, a subpoena for documents by the U.S. Department of Justice and its exposure to coal.

In November, London-listed Katanga halted exports from its Kamoto Project in Congo after finding traces of uranium in the product.

Citi analysts said in a note they expect a single digit percentage downgrade to 2018 consensus earnings expectations after Glencore's "mixed" production performance.

Glencore reiterated that its copper output in 2019 is projected to reach 1.54 million tonnes and cobalt 57,000 tonnes.

(Reporting by Zandi Shabalala; editing by Jason Neely)