Copper and cobalt producers in the Democratic Republic of Congo are tightening supply checks and weighing production adjustments after chemical disruptions linked to the Iran war hit shipments, according to a Reuters report. The disruption is affecting supplies of sulfuric acid and sulfur-based chemicals used in mineral processing, forcing some miners to conserve stocks while assessing how long existing inventories can last.

The pressure comes at a delicate moment for Congo’s cobalt sector, which was already operating under export controls. In late March, Congo’s regulator said miners must use outstanding fourth-quarter 2025 export quotas by April 30, while first-quarter 2026 quotas can be shipped until June 30, according to a separate Reuters report on the quota timeline.

That has left producers balancing shipping deadlines with fresh uncertainty over the chemicals needed to process output.

Industry sources said some orders for sodium metabisulfite were cancelled or withdrawn after contracts had already been signed, while buyers have stepped up physical verification of warehouse stocks and ownership documents before committing to purchases. The response reflects growing concern that longer transit times, rerouted cargo and tighter freight availability could deepen shortages in the weeks ahead.

The stakes extend beyond Congo’s mining belt. The DRC remains central to global cobalt supply, with USGS data showing the country accounts for more than half of world cobalt production, making any disruption closely watched across battery and clean-energy supply chains, according to USGS research.

For now, the immediate next step for miners is not expansion but preservation: protect remaining chemical stocks, verify incoming supply, and decide whether output cuts become necessary if disruptions persist.