The firm posted a net loss of $676 million (£431.8m) for the first half, compared with a $1.7 billion profit a year earlier.
Along with its rivals, Glencore has suffered from large price falls over the past year across a range of commodities, triggered by the slowing Chinese economy, but its results were also undermined by $792m of costs related to the slow development of its Chad oil operations.
However, chief executive Ivan Glasenberg said: “We remain by far the most diversified commodity producer and marketer and are well positioned to benefit from any improvement in pricing when it finally and inevitably materialises.
“Our principal objective remains to grow our free cash flow per share and return any excess capital in the most sustainable and efficient manner.”
Analysts at SP Angel said that the first-half results from Glencore had highlighted the FTSE 100 group’s exposure to copper, prices for which have fallen to a fresh six-year low amid “aggressive” short-selling activity by Chinese hedge fund managers and are expected to remain under pressure in the second half of the year.
The broker added: “We are disappointed with these results and are concerned that, if China does not move to stimulate domestic construction, infrastructure and other industrial activity, Glencore could also disappoint through the second half.”