Production across all commodities is in line with expectations in the first quarter of this year, the company said, and the ramp-up of its Katanga copper and cobalt mine in Democratic Republic of Congo is on track.

That helped to take Glencore's copper output to 345,000 tonnes in the quarter, up 7 percent year on year.

Production of cobalt, a copper by-product that is in demand for battery metals, rose 11 percent to 7,000 tonnes.

At the start of February Glencore predicted full-year copper output should reach nearly 1.5 million tonnes because its Katanga mine should add about 150,000 tonnes, as well as 11,600 tonnes of cobalt.

The company said in February that 2018 earnings before interest and tax at its marketing, or trading, division would be between $2.2 billion and $3.2 billion, which its finance chief said was deliberately conservative in view of past commodity price crashes.

During the 2015 slump, Glencore reduced output of commodities including zinc and copper and shut mining operations in Congo for an upgrade.

The Katanga mine is the subject of legal wrangling with state miner Gecamines, which has begun legal proceedings to dissolve a Glencore copper and cobalt joint venture that operates there.

In addition, Ventora, a company affiliated with Israeli billionaire Dan Gertler, has served freezing orders on Glencore for unpaid royalties of nearly $3 billion.

Glencore has said it will contest the legal actions, while analysts have said that any disruption, especially of the cobalt market, would have a massive effect on physical commodity markets. The uncertainty over Democratic Republic of Congo has weighed on the shares of Glencore, which are lagging behind the other major miners this year.

On Thursday they were up by about 1 percent at 0710 GMT.

Analysts said the results were in line so far. Bernstein's Paul Gait said the marketing guidance "should be an incremental comfort to those who continue to be concerned about the marketing business" and restated his "outpeform" rating.

(Reporting by Barbara Lewis and Arathy Nair; Editing by David Goodman)